Aminomethyl substituted thieno[2,3- d ]pyrimidines as adenosine A2A receptor antagonists

Brian C. Shook; Devraj Charavarty; J. Kent Barbay; Aihua Wang; Kristi Leonard; Vernon Alford; Mark Powell; Derek A. Beauchamp; Stefanie Rassnick; Robert Scannevin; Karen Carroll; Nathaniel Wallace; Jeffrey Crooke; Mark Ault; Lisa Lampron; Lori Westover; Kenneth Rhodes; Paul F. Jackson

doi:10.1039/C1MD00082A

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DOI: 10.1039/C1MD00082A (Concise Article) Med. Chem. Commun., 2011, 2, 950-965

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Aminomethyl substituted thieno[2,3-d]pyrimidines as adenosine A_2A receptor antagonists

Brian C. Shook *^a, Devraj Charavarty ^a, J. Kent Barbay ^a, Aihua Wang ^a, Kristi Leonard ^a, Vernon Alford ^a, Mark Powell ^a, Derek A. Beauchamp ^a, Stefanie Rassnick ^b, Robert Scannevin ^b, Karen Carroll ^b, Nathaniel Wallace ^b, Jeffrey Crooke ^b, Mark Ault ^b, Lisa Lampron ^b, Lori Westover ^b, Kenneth Rhodes ^b and Paul F. Jackson ^a
^aMedicinal Chemistry, Johnson & Johnson PRD, Welsh and McKean Roads, P.O. Box 776, Spring House, PA 19477, USA. E-mail: bshook@its.jnj.com; Fax: +1 215-540-4612; Tel: +1 215-628-7047
^bCNS Biology, Johnson & Johnson PRD, Welsh and McKean Roads, P.O. Box 776, Spring House, PA 19477, USA

Received 22nd March 2011 , Accepted 22nd April 2011

First published on 19th May 2011

Abstract

A novel series of aminomethyl substituted thieno[2,3-d]pyrimidines have been identified as adenosine A_2A receptor antagonists. Analogues show excellent in vitro activities and have excellent activity in vivo in mouse models of Parkinson's disease.

Introduction

Parkinson's disease (PD) is a chronic, progressive neurological disease that affects ∼1% of the population over the age of 65.¹ It is characterized by progressive impairment in motor function caused by gradual loss of dopamine (DA) producing neurons in ventral midbrain and concomitant loss of DA input into the striatum.^2,3 The loss of DA input leads to dysregulation of striatal function and the classic motor symptoms of PD, such as resting tremor, muscular rigidity and bradykinesia. The impairment of motor function is often accompanied by anxiety, depression and cognitive impairment.

Most treatments for PD focus on restoring dopamine signaling to reduce the severity of the motor symptoms.⁴Dopamine replacement therapy using L-DOPA, the precursor to dopamine, remains the gold-standard treatment for PD. Although the dopamine targeted therapies work well to address the motor impairments of PD, they all produce undesirable side effects (dyskinesia, hallucinations, on–off effects) that become more severe with continued treatment. This type of therapy has reduced efficacy as the disease progresses and does not address the co-morbidities associated with PD like mood disturbances, postural instability and cognitive impairment.

As a result of these limitations many drug companies have sought non-dopamine based therapies for PD. One approach that has received considerable attention is modulation of adenosine receptors.⁵Adenosine is a neuromodulator that coordinates responses to dopamine and other neurotransmitters in areas of the brain that are responsible for motor function, learning and memory.⁶Adenosine is comprised of four distinct sub-types designated A₁, A_2A, A_2B, and A₃.⁷ Both A_2A and A₁ receptors are highly expressed in the brain, particularly striatum, while A_2B and A₃ receptors are not.⁸ In the striatum A_2A receptors co-localize and physically associate with dopamine D₂ receptors.^2,3A_2A and D₂ receptors have opposing effects on adenylate cyclase and cAMP production in cells such that A_2A receptor antagonists enhance D₂ dependent signaling. Of importance to PD, pharmacological blockade of A_2A receptors had shown dramatic beneficial effects in preclinical animal models of PD. In fact, several selective A_2A antagonists have advanced into clinical development.⁹

There have been several reports published suggesting that adenosine A₁antagonists may improve learning and memory.¹⁰ This would suggest that a dual A_2A/A₁antagonist may offer improved benefit to PD patients as it is known that cognitive deficiencies increase as the disease progresses.¹¹ Unfortunately, it is unknown what balance of A₁vs.A_2A antagonism would be ideal for PD patient benefit. We would like to report herein a novel series of thieno[2,3-d]pyrimidines as selective A_2A and dual A_2A/A₁receptor antagonists for the potential treatment of PD.

Results and discussion

Initial lead generation, through a de novo approach, led to a series of aminomethyl thieno[2,3-d]pyrimidines that were potent adenosine A_2A receptor antagonist with varying degrees of selectivity against adenosine A₁ receptors and are represented generically by structure 4 (Scheme 1). The compounds were synthesized starting from the commercially available aminonitrile 1 and reacting with various aryl and heteroaryl nitriles by heating with a catalytic amount of t-BuOK in dioxane.¹² The resulting aminopyrimidine 2 was oxidized to the corresponding aldehyde 3 using SeO₂ (Path 1), that underwent reductive amination with a variety of amines to give the target compound 4. An alternative route (Path 2) was developed to prepare the target compounds where the aminopyrimidine 2 was protected using excess (Boc)₂O in the presence of 4-dimethylamino pyridine (DMAP) to give compound 5. Radical bromination of the methyl group using N-bromosuccinimide (NBS) gave the corresponding bromide 6. The Boc protecting groups were removed with TFA and the resulting bromide was alkylated with a variety of amines to provide the target compounds. This route proved to be helpful for incorporating hindered secondary amines.


	Scheme 1 Synthesis of aminomethyl substituted thieno[2,3-d]pyrimidines.

A third synthetic route was also used to install aryl and heteroaryl substituents that contained methyl groups to avoid mixtures of oxidized or brominated products that would be obtained from the paths outlined in Scheme 1. The aminonitrile 7 was condensed with a variety of heteroaryl nitriles to afford an intermediate aminopyrimidine that was brominated using NBS to afford 8 (Scheme 2). Bromide 8 was converted to the corresponding vinyl intermediate 9 under standard Suzuki conditions using the corresponding vinyl boronic ester. Dihydroxylation using AD-mix followed by oxidation with periodic acid (HIO₄) afforded the aldehyde 3. Reductive amination with a variety of amines affords the target compounds 4.


	Scheme 2 Synthesis of compounds where R¹ contains a methyl group.

We started exploring a variety of amines by keeping the right hand portion of the molecule as 2-substituted furan or 2-substituted-5-methylfuran, two heterocycles that were identified that gave good in vitro potency (Table 1). The acyclic amines (10–13) showed modest functional activity against A_2A but weak activity for A₁ receptors. Cyclopropyl amine 12 did not show any activity in reversing haloperidol induced catalepsy in mice, which was our primary in vivo screening model.¹³ Greater than 50% reversal of catalepsy indicates a positive result in the catalepsy model (see Experimental section for more details). The very basic pyrrolidines and piperidine analogues (14–16) showed slightly increased activity for A_2Ain vitro, but showed no effect in vivo reversing haloperidol induced catalepsy in mice at 10 mg kg⁻¹, p.o. Interestingly, the less basic morpholine analogues 18 and 19 did show good in vivo activity with 18 having an ED₅₀ = 1.3 mg kg⁻¹. The calculated pK_a's¹⁴ for the pyrrolidine 14 and piperidine 16 were 8.2 and 8.5, respectively, while the less basic morpholine analogue 18 has a calculated pK_a of 6.5. With a possible trend being identified our focus was to examine the in vitro and in vivo activity of analogues containing less basic amino substituents. We thought that this approach would increase log P values and potentially increase blood brain barrier (BBB) penetration which would increase in vivo activity.

Table 1 A_2A and A₁ activity for furan and 5-methylfuran analogs


Compound	NRR′	R	A_2A K_i/nM	A₁K_i/nM	Mouse catalepsy activity^a^,^b	Compound	NRR′	R	A_2A K_i/nM	A₁K_i/nM	Mouse catalepsy activity^a^,^b
a Results are reported as an ED₅₀, active/not active at a single dose or (—) for not tested. b Active is at least 50% reversal of cataleptic activity.
10		H	140 ± 5	3550 ± 409	—	21		H	6.5 ± 0.9	150 ± 9	ED₅₀ < 3.0 mg kg⁻¹
11		H	55.5 ± 7.4	2130 ± 176	—	22		H	19.7 ± 2.9	740 ± 69	ED₅₀ < 1.0 mg kg⁻¹
12		H	36.0 ± 3.4	1890 ± 96	Not active at 10 mg kg⁻¹	23		H	49.6 ± 4.3	2230 ± 208	Active at 10 mg kg⁻¹
13		H	170 ± 13	2480 ± 100	—	24		H	6.6 ± 1.0	290 ± 42	ED₅₀ < 1.0 mg kg⁻¹
14		H	28.1 ± 3.7	6430 ± 860	Not active at 10 mg kg⁻¹	25		H	5.3 ± 0.7	100 ± 16	Active at 10 mg kg⁻¹
15		Me	26.1 ± 2.2	620 ± 96	Not active at 10 mg kg⁻¹	26		H	300 ± 8	4000 ± 365	—
16		Me	28.8 ± 8.1	610 ± 123	Not active at 10 mg kg⁻¹	27		H	230 ± 17	2720 ± 188	—
17		H	27.6 ± 1.8	1170 ± 304	—	28		H	9.2 ± 2.1	369 ± 66	ED₅₀ = 3.2 mg kg⁻¹
18		H	29.0 ± 2.0	1680 ± 177	ED₅₀ = 1.3 mg kg⁻¹	29		H	7.2 ± 1.0	290 ± 10	ED₅₀ < 0.1 mg kg⁻¹
19		Me	32.8 ± 3.9	1050 ± 88	Active at 10 mg kg⁻¹	30		H	10.3 ± 2.6	1340 ± 102	Not active at 10 mg kg⁻¹
20		Me	200 ± 21	3320 ± 131	—	31		H	8.7 ± 1.3	1240 ± 307	ED₅₀ = 10.0 mg kg⁻¹

The unsaturated piperidine 21 (calc. pK_a = 7.2) was significantly less basic than the saturated compound 16 (calc. pK_a = 8.5) and resulted in a 4-fold increase in A_2A activity, but more importantly was very potent in vivo having an ED₅₀ < 3.0 mg kg⁻¹, p.o (Table 1). The fluorinated piperidines 22–24 also showed excellent in vitro and in vivo activity. The calculated pK_a's for the fluorinated piperidines 22–24 are 7.0, 5.5, and 4.7, respectively, and are also significantly lower than the pK_a's for the corresponding pyrrolidine and piperidine analogues. The cis-2,6-dimethylpiperidine 25 (calc. pK_a = 8.5)¹⁵ proved to be the most potent group for both A_2A and A₁ activity while maintaining activity in vivo at 10 mg kg⁻¹. The thiomorpholine analog 28 (calc. pK_a = 6.7) also showed good in vitro potency and had an in vivoED₅₀ = 3.2 mg kg⁻¹. The pyrroline 29 (calc. pK_a = 6.8) was the most potent compound in vivo having an ED₅₀ < 0.1 mg kg⁻¹. The fluorinated pyrrolidines 30 (calc. pK_a = 5.9) and 31 (calc. pK_a = 3.3) maintained good activity in vitro against A_2A but were less effective in vivo compared to the fluorinated piperidines 22 and 24 despite having comparable pK_a values.

With a good handle on the amino substituents we wanted to further explore the scope of the furan substituent. Although the mono-substituted furans showed excellent in vitro and in vivo activity, mono-substituted furans are potential metabolic liabilities. The furan replacement strategy has also been reported in other chemical scaffolds of A_2A receptor antagonists.¹⁶ In addition, several of the compounds from Table 1 had low metabolic stability in human liver microsomes (HLM) and short in vivo half-lives in rodent. Therefore, the alkyl substituent on the furan was extended from methyl to ethyl, isopropyl, cyclopropyl and CHF₂ (32–42), and chloro- and bromo-substituted furans (43–53) were also prepared (Table 2). The majority of aryl and heteroaryl nitriles were commercially available except propyl, cyclopropyl and CHF₂ substituted 2-furanonitriles. The substituted furan nitriles that were not available were synthesized via the corresponding bromide 51 as indicated in Scheme 3.^12,17 The bromide 54, prepared viaScheme 1, was converted to the alkyl substituent, shown in 55, via a Suzuki or Negishi reaction using the appropriate boronic acid or alkyl zinc reagents. The aldehyde 56 was converted to the corresponding difluoride 57 using (diethylamino)sulfur trifluoride (DAST) which was incorporated into the thienopyrimidines as outlined in Scheme 1.¹²

Table 2 A_2A and A₁ activity for 5-substituted furan analogs


Compound	NRR′	R	A_2A K_i/nM	A₁K_i/nM	Mouse catalepsy activity^a^,^b	Compound	NRR′	R	A_2A K_i/nM	A₁K_i/nM	Mouse catalepsy activity^a^,^b
a Results are reported as an ED₅₀, active/not active at a single dose or (—) for not tested. b Active is at least 50% reversal of cataleptic activity.
32		Et	78.9 ± 10.1	>610	—	43		Cl	22.2 ±.3.5	710 ± 55	Not active at 10 mg kg⁻¹
33		Et	25.2 ± 4.4	190 ± 17	—	44		Cl	33.4 ± 3.7	1420 ± 175	Active at 10 mg kg⁻¹
34		i-Pr	>1360	>600	—	45		Cl	45.4 ± 7.4	640 ± 34	—
35		i-Pr	17.0 ± 2.4	140 ± 17	Not active at 10 mg kg⁻¹	46		Cl	36.7.± 3.5	1080 ± 293	Active at 10 mg kg⁻¹
36			960 ± 78	>1100	—	47		Cl	9.1 ± 1.2	188 ± 27	Active at 10 mg kg⁻¹
37			110 ± 10	330 ± 36	—	48		Cl	11.0 ± 0.8	190 ± 18	active at 10 mg kg⁻¹
38		CHF₂	30.8 ± 3.7	2700 ± 220	Not active at 10 mg kg⁻¹	49		Cl	10.0 ± 0.5	780 ± 100	Not active at 10 mg kg⁻¹
39		CHF₂	28.6 ± 2.0	730 ± 105	Not active at 10 mg kg⁻¹	50		Cl	15.9 ± 2.9	245 ± 14	—
40		CHF₂	42.2 ± 6.7	1670 ± 354	—	51		Br	22.5 ± 4.5	710 ± 76	Not active at 10 mg kg⁻¹
41		CHF₂	610 ± 33	17820 ± 798	—	52		Br	30.0 ± 4.0	725 ± 102	Active at 10 mg kg⁻¹
42		CHF₂	43.2 ± 6.2	2100 ± 99	—	53		Br	12.1 ± 3.1	40.2 ± 20.2	—


	Scheme 3 Synthesis of substituted furans.

We chose morpholine and cis-2,6-dimethylpiperidine as the amines to explore the new substitutions and it was clear that the cis-2,6-dimethylpiperidine analogues are generally more potent than their corresponding morpholine analogues (comparing 32–39), but they are still less potent than the corresponding unsubstituted furan 25 (Table 1). Unfortunately, this was also true when comparing the in vivo activity of 25 and 35, or comparing 18 and 38, where 18 is much more active in reversing catalepsy in mice. This decrease in activity in vivo for 35 and 39 could possibly be explained by the 3–5 fold decrease in A_2A functional activity compared to the corresponding unsubstituted analogue 25. However, the inactivity of 38 and the potent activity of the unsubstituted analogue 18 cannot be explained similarly and is surprising considering the comparable in vitro activity, 30.8 and 29.0 nM, respectively.

We also explored chloro- and bromo-substituted furans in compounds 43–53. In general they all maintained good in vitro activity for A_2A, but also had decreased activity in vivo for those tested against their corresponding unsubstituted furan analogs. The pyrrolidine 43 had no activity in vivo at 10 mg kg⁻¹ which was consistent with the results obtained from 14 and 15. The piperidines 46–48 and morpholine 52 were all active in vivo at 10 mg kg⁻¹, p.o. Interestingly, the pyrroline 49 was not active at 10 mg kg⁻¹ which was in stark contrast to the des-Cl analogue 29 which had an ED₅₀ < 0.1 mg kg⁻¹. The general decrease in potency in vivo for the alkyl, chloro- and bromo-substituted furan compounds is surprising given the similar in vitro potencies, but was consistent for all compounds.

Next we explored replacement of the furan with various 5-membered heterocycles (Table 3). The 2-substituted oxazoles 58–60 were significantly less potent (12–40 fold) in vitro against A_2A than their corresponding 2-substituted furan analogs 18, 29, and 21, respectively. This was much to our surprise as the replacement of just one atom resulted in such a dramatic loss in activity. Likewise the thiazole 61, methyl thiazoles 62 and 63, isoxazoles 64 and 65, thiophenes 66 and 67, and oxazoles 68 and 69 all had similar decreases in A_2A activity compared to their corresponding furan analogues. Even the benzofuran 70 had significantly decreased in vitro activity. This was somewhat discouraging that the furan was an ideal substituent and could not be readily replaced with other 5-membered heterocycles.

Table 3 A_2A and A₁ activity for 5-membered heterocyclic analogs


Compound	NRR′	Het	A_2A K_i/nM	A₁K_i/nM
58			360 ± 28	3250 ± 310
59			240 ± 22	3890 ± 267
60			240 ± 13	2960 ± 403
61			250 ± 17	2730 ± 167
62			210 ± 12	>930
63			89.1 ± 8.6	300 ± 24
64			1010 ± 30	680 ± 30
65			130 ± 7	500 ± 19
66			110 ± 7	>10000
67			125 ± 5	1020 ± 220
68			238 ± 12	3895 ± 352
69			240 ± 10	2964 ± 311
70			350 ± 17	630 ± 79

After exploring various heterocyclic replacements for the furan, we decided to explore aryl substituents (Table 4). The phenyl substituted analog 71 was a starting point for us despite the modest A_2A activity. Interestingly, fluorine or chlorine substituted in the meta-position gave nearly a 10-fold increase in A_2A activity. Further exploration at the meta-position revealed that a cyano group in that position was ideal and gave the most potent compounds (76–84) against A_2A. The less basic amines gave the best activity for A_2A similar to compounds having the furan substituent. Very basic groups like pyrrolidine 83 were not well tolerated and resulted in no activity against A_2A although it had decent A₁ activity at 130 nM. The less basic compounds 77, 79 and 80 all had very potent activity in vivo ED₅₀'s < 1 mg kg⁻¹. Moving the cyano group to the ortho (85) or para (86–88) positions resulted in decreased in vitro activity against A_2A. Other electron withdrawing groups at the meta position like CF₃, SO₂Me, NO₂, and CONMe₂ decreased A_2A activity significantly. A methoxy group (96–98) in the meta position had modest activity for A_2A but still less than that obtained from the cyano group.

Table 4 A_2A and A₁ activity for aryl substituted analogs


Compound	NR¹R²	R³	A_2AK_i/nM	A₁K_i/nM	Mouse catalepsy activity^a^,^b	Compound	NR¹R²	R³	A_2A K_i/nM	A₁K_i/nM	Mouse catalepsy activity^a^,^b
a Results are reported as an ED₅₀, active/not active at a single dose or (—) for not tested. b Active is at least 50% reversal of cataleptic activity.
71		H	995 ± 57	>5000	—	85		2–CN	1030 ± 77	5050 ± 333	—
72		3-F	110 ± 8	620 ± 29	—	86		4–CN	390 ± 25	8430 ± 664	—
73		3-Cl	120 ± 8	790 ± 50	—	87		4–CN	180 ± 20	1630 ± 219	—
74		3,5-diF	350 ± 29	2300 ± 235	—	88		4–CN	79.2 ± 10.2	2350 ± 165	—
75		3,4-diF	360 ± 45	2890 ± 314	—	89		3–CF₃	1070 ± 86	2960 ± 344	—
76		3–CN	83.5 ± 8.8	2070 ± 310	—	90		3–CF₃	>10000	3030 ± 277	—
77		3–CN	36.1 ± 5.4	1010 ± 87	ED₅₀ < 1.0 mg kg⁻¹	91		4–CF₃	>10000	3560 ± 423	—
78		3–CN	64.6 ± 4.4	460 ± 67	—	92		2–CF₃	>10000	>10000	—
79		3–CN	54.4 ± 6.1	2950 ± 355	ED₅₀ < 1.0 mg kg⁻¹	93		3–SO_2Me	>10000	>10000	—
80		3–CN	39.0 ± 4.0	840 ± 36	ED₅₀ < 1.0 mg kg⁻¹	94		3–NO₂	3760 ± 309	>10000	—
81		3–CN	50.9 ± 2.3	980 ± 80	Active at 10 mg kg⁻¹	95		3-CONMe₂	2250 ± 297	> 10000	—
82		3–CN	13.2 ± 3.0	210 ± 52	Active at 10 mg kg⁻¹	96		3-OMe	300 ±.31	3220 ± 200	—
83		3–CN	>10000	130 ± 18	—	97		3-OMe	370 ± 23	2990 ± 189	—
84		3–CN	150 ± 13	1070 ± 60	—	98		3-OMe	97.7 ± 12.6	1810 ± 323	—

Conclusions

A novel series of aminomethyl substituted thieno[2,3-d]pyrimidines was developed as potent adenosine A_2A receptor antagonists. The 2-substituted furans and 2-substituted-5-methyl furans were ideal groups for optimal potency in vitro and in vivo. Investigation of a wide variety of cyclic and acyclic amines revealed some interesting SAR in vivo. The less basic amino substituents in general gave slightly more potent in vitro activity, but proved to be essential for potent in vivo activity. To expand the SAR we chose a few of the better amino substituents to keep constant while we tried to modify the furan portion of the molecule. Replacement of furan with various 5-membered heterocycles significantly decreased A_2A activity. Surprisingly the furan could be replaced with meta-substituted phenyl groups and maintain good in vitro activity against A_2A. The 3-cyanophenyl substituent proved to be the ideal group for in vitro A_2A activity as well as in vivo activity.

Experimental

Reagent grade chemicals and solvents were purchased from commercial suppliers and used without further purification. All chromatography was performed on silica gel and were carried out on a combi-flash system equipped with an automated fraction collector. High resolution MS was performed on a JEOL Accutof JMS-T100 LC with a DART CE ionization source operating in the positive mode. All proton nuclear magnetic resonance spectra were determined using a 300 or 400 MHz Bruker NMR with the appropriate internal standards, and chemical shifts are reported in ppm relative to TMS. Defined J values are reported in Hz. All final compounds were purified to ≥95% purity as determined by Agilent 1100 series high performance liquid chromatography (HPLC) with UV detection at 254 nm using the following method: Supelcosil ABZ + PLUS, 3.3 cm × 2.1 cm, 11 min; 1.2 mL min⁻¹ flow rate; 5–95% 0.1% TFA in CH₃CN/0.1% TFA in H₂O.

Compound 18: 2-furan-2-yl-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Solid potassium-tert-butoxide (325 mg, 2.9 mmol) was added to a dioxane solution (7 mL) of 2-amino-5-methyl-thiophene-3-carbonitrile (2.0 g, 14.5 mmol) and furan-2-carbonitrile (1.3 g, 14.5 mmol). The resulting mixture was heated in an oil bath at 130 °C for 10 minutes. The dark slurry was cooled to room temperature, diluted with THF, and dry packed onto silica gel. The material was then purified viacolumn chromatography to give 1.6 g of 2-furan-2-yl-6-methyl-thieno[2,3-d]pyrimidin-4-ylamine.

Solid SeO₂ (4.3 g, 39.0 mmol) was added to a dioxane (50 mL)/water (0.5 mL) suspension of 2-furan-2-yl-6-methyl-thieno[2,3-d]pyrimidin-4-ylamine (3.0 g, 13.0 mmol) and the mixture was heated to 100 °C. After 20 h the mixture was filtered hot and diluted with EtOAc. The organic phase was washed with water and brine, dried (Na₂SO₄) and dry packed onto silica gel. Column chromatography gave 1.7 g of 4-amino-2-(furan-2-yl)thieno[2,3-d]pyrimidine-6-carbaldehyde.

Solid NaBH(OAc)₃ (173 mg, 0.82 mmol) was added to a THF solution (4 mL) of 4-amino-2-(furan-2-yl)thieno[2,3-d]pyrimidine-6-carbaldehyde (100 mg, 0.41 mmol) and morpholine (72 μL, 0.82 mmol) and the mixture was heated to 45 °C. After 16 h the mixture was cooled, diluted with EtOAc, washed with saturated aqueous NaHCO₃, water and brine, dried (Na₂SO₄), and dry packed onto silica gel. Column chromatography gave 90 mg of 2-furan-2-yl-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine 18. ¹H NMR (DMSO-d₆, 300 MHz): δ = 7.81 (1H, s), 7.50 (2H, s), 7.41 (1H, s), 7.11 (1H, d, J 3.4), 6.51–6.72 (1H, m), 3.71 (2H, s), 3.60 (4H, t, J 4.3), 2.44 (4H, br. s); MSm/z 317 (M + H). HRMS calcd for C₁₅H₁₆N₄O₂S 316.0994, found 317.1051 (M⁺ + H)

The procedure used to prepare compound 18 was also used to prepare the following compounds with the appropriate amine substituent. Also, the corresponding nitrile replacement for the furan-2-carbonitrile is specified where appropriate.

Compound 10: 6-dimethylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.59 (1H, s), 7.20–7.33 (1H, m), 7.12 (1H, s), 6.55 (1H, dd, J 3.4, 1.9), 5.82 (2H, br. s), 3.78 (2H, s), 2.38 (6H, s); MSm/z 275 (M + H).

Compound 11: 6-diethylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.59 (1H, dd, J 1.7, 0.9), 7.25 (1H, dd, J 3.5, 0.8), 6.96 (1H, s), 6.54 (1H, dd, J 3.4, 1.7), 5.28 (2H, br. s), 3.83 (2H, s), 2.61 (4H, q, J 7.2), 1.08 (6H, t, J 7.2); MSm/z 303 (M + H).

Compound 12: 6-cyclopropylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.60 (1H, d, J 0.8), 7.25 (1H, s), 6.99 (1H, s), 6.55 (1H, dd, J 3.5, 1.8), 5.42 (2H, br. s), 4.09 (2H, s), 2.15–2.32 (1H, m), 0.33–0.56 (4H, m); MSm/z 287 (M + H).

Compound 13: 6-cyclohexylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.59 (1H, d, J 0.8), 7.24 (1H, d, J 3.4), 7.06 (1H, s), 6.54 (1H, dd, J 3.4, 1.7), 5.44 (2H, br. s), 4.05–4.13 (2H, m), 3.49 (1H, s), 2.52–2.66 (1H, m), 2.06 (2H, s), 1.73 (2H, br. s), 1.06–1.35 (6H, m); MSm/z 329 (M + H).

Compound 14: 2-furan-2-yl-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (400 MHz, chloroform-d): δ_H 7.59 (1H, s), 7.25 (1H, d, J 3.3), 7.06 (1H, s), 6.54 (1H, dd, J 3.3, 1.8), 5.44 (2H, br. s), 3.92 (2H, s), 2.61–2.74 (4H, m), 1.85 (4H, dt, J 6.8, 3.3); MSm/z 301 (M + H).

Compound 17: 6-(azepan-1-ylmethyl)-2-(furan-2-yl)thieno[2,3-d]pyrimidin-4-amine

MS m/z 329 (M + H).

Compound 20: 6-(3,4-dihydro-1H-isoquinolin-2-ylmethyl)-2-(5-methyl-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.06–7.23 (4H, m), 6.95–7.04 (2H, m), 6.14 (1H, dd, J 3.3, 0.8), 5.35 (2H, br. s), 3.91 (2H, s), 3.74 (2H, s), 2.91 (3H, t, J 5.3), 2.82 (2H, t, J 5.5); MSm/z 377 (M + H).

Compound 21: 6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.60 (1H, s), 7.25 (1H, s), 7.00 (1H, s), 6.55 (1H, dd, J 3.4, 1.9), 5.77 (1H, br. s), 5.69 (1H, br. s), 5.25 (2H, br. s), 3.83 (2H, s), 2.99–3.16 (2H, m), 2.64 (2H, t, J 5.7), 2.12–2.26 (2H, m); MSm/z 313 (M + H).

Compound 22: 6-(4-fluoro-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, DMSO-d₆): δ_H 7.93 (1H, br. s), 7.72 (1H, s), 7.24 (1H, d, J 3.4), 6.70 (1H, d, J 3.4), 4.64 (2H, br. s), 3.35 (1H, m), 3.16 (4H, br. s), 2.08 (4H, br. s); MSm/z 333 (M + H).

Compound 23: 6-(4,4-difluoro-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.59 (1H, s), 7.26 (1H, d, J 3.4), 6.96 (1H, s), 6.55 (1H, dd, J 3.4, 1.5), 5.46 (2H, s), 3.78 (2H, s), 2.63 (4H, t, J 5.5), 1.91–2.11 (4H, m); MSm/z 351 (M + H).

Compound 24: 6-(3,3-difluoro-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, acetone-d₆): δ_H 7.70 (1H, s), 7.36 (1H, s), 7.16 (1H, d, J 3.4), 6.79 (2H, br. s), 6.59 (1H, dd, J 3.4, 1.9), 3.74 (2H, s), 3.63 (2H, br. s), 2.13–2.31 (2H, m), 1.83 (2H, dd, J 12.6, 3.6), 1.46–1.65 (2H, m); MSm/z 351 (M + H). HRMS calcd for C₁₆H₁₆F₂N₄OS 350.1013, found 350.1066 (M⁺ + H).

Compound 25: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.59 (1H, s), 7.25 (1H, d, J 3.4), 6.95 (1H, s), 6.55 (1H, dd, J 3.4, 1.5), 5.32 (2H, br. s) 4.11 (2H, s), 2.56 (2H, br. s), 1.76 (2H, br. s), 1.52–1.70 (4H, m), 1.21 (3H, s), 1.19 (3H, s); MSm/z 343 (M + H). HRMS calcd for C₁₈H₂₂N₄OS 342.1514, found 343.1621 (M⁺ + H).

Compound 26: 1-(4-amino-2-furan-2-yl-thieno[2,3-d]pyrimidin-6-ylmethyl)-piperidin-4-ol

¹H NMR (300 MHz, chloroform-d): δ_H 7.60 (1H, s), 7.25 (1H, s), 6.99 (1H, s), 6.55 (1H, dd, J 3.4, 1.9), 5.33 (2H, br. s), 3.85 (2H, s), 2.75 (2H, t, J 11.1), 2.56 (2H, t, J 5.3), 1.70–1.99 (5H, m); MSm/z 331 (M + H).

Compound 27: 1-(4-amino-2-furan-2-yl-thieno[2,3-d]pyrimidin-6-ylmethyl)-piperidin-4-one

¹H NMR (300 MHz, chloroform-d): δ_H 7.60 (1H, s), 7.26 (1H, s), 7.00 (1H, s), 6.55 (1H, dd, J 3.4, 1.5), 5.47 (2H, s), 3.86 (2H, s), 2.84 (4H, t, J 6.0), 2.49 (4H, t, J 6.0); MSm/z 329 (M + H).

Compound 28: 2-(furan-2-yl)-6-(thiomorpholinomethyl)thieno[2,3-d]pyrimidin-4-amine

¹H NMR (300 MHz, chloroform-d): δ_H 7.58 (1H, s), 7.21–7.32 (1H, m), 7.12 (1H, s), 6.55 (1H, dd, J 3.4, 1.9), 5.79 (2H, br. s), 3.80 (2H, s), 2.75–2.84 (4H, m), 2.67–2.73 (4H, m); MSm/z 333 (M + H).

Compound 29: 6-((2,5-dihydro-1H-pyrrol-1-yl)methyl)-2-(furan-2-yl)thieno[2,3-d]pyrimidin-4-amine

¹H NMR (300 MHz, chloroform-d): δ_H 7.59 (1H, s), 7.20–7.33 (1H, m), 7.12 (1H, s), 6.55 (1H, dd, J 3.4, 1.9), 5.82 (2H, s), 5.77 (2H, br. s), 3.78 (2H, s), 3.62 (4H, m); MSm/z 299 (M + H).

Compound 30: 6-(3-fluoro-pyrrolidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.60 (1H, s), 7.25 (1H, d, J 3.4), 6.99 (1H, s), 6.55 (1H, dd, J 3.4, 1.9), 5.34 (2H, br. s), 5.20–5.32 (1H, m), 3.92 (2H, s), 2.93–2.98 (1H, m), 2.82–2.94 (2H, m), 2.57–2.68 (1H, m), 2.06–2.27 (2H, m); MSm/z 319 (M + H).

Compound 31: 6-(3,3-difluoro-pyrrolidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, DMSO-d₆): δ_H 7.82 (1H, s), 7.54 (2H, s), 7.42 (1H, s), 7.12 (1H, d, J 3.4 Hz), 6.63 (1H, dd, J 3.4, 1.9), 3.88 (2H, s), 2.97 (2H, t, J 13.4), 2.80 (2H, t, J 7.0), 2.13–2.40 (2H, m); MSm/z 337 (M + H).

Compound 43: 2-(5-chloro-furan-2-yl)-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

5-Chlorofuran-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, DMSO-d₆): δ_H 7.65 (1H br. s), 7.18 (1H, d, J 3.8), 6.67 (1H, d, J 3.4), 3.99 (2H, br. s), 2.68 (4H, m), 1.66–1.89 (4H, m); MSm/z 335 (M + H).

Compound 44: 6-azepan-1-ylmethyl-2-(5-chloro-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

5-Chlorofuran-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, DMSO-d₆): δ_H 7.74 (1H, s), 7.24 (1H, br. s), 6.79 (1H, s), 4.61 (2H, br. s), 4.50 (2H, br. s), 3.38 (2H, br. s), 3.13 (4H, br. s), 1.84 (4H, br. s), 1.63 (4H, br. s); MSm/z 363 (M + H).

Compound 46: 2-(5-chloro-furan-2-yl)-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

5-Chlorofuran-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, DMSO-d₆): δ_H 7.72 (1H, s), 7.24 (1H, d, J 3.4), 6.70 (1H, d, J 3.4), 4.64 (2H, br. s), 3.35 (1H, br. s), 3.16 (4H, br. s), 2.08 ppm (4H, br. s); MSm/z 367 (M + H).

Compound 48: 2-(5-chloro-furan-2-yl)-6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

5-Chlorofuran-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.22 (1H, d, J 3.4), 7.00 (1H, s), 6.33 (1H, d, J 3.4 Hz), 5.73–5.85 (1H, m), 5.60–5.73 (1H, m), 5.29 (2H, br. s), 3.83 (2H, s), 3.04–3.15 (2H, m), 2.64 (2H, t, J 5.8), 2.14–2.25 (2H, m); MSm/z 347 (M + H).

Compound 49: 2-(5-chloro-furan-2-yl)-6-(2,5-dihydro-pyrrol-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

5-Chlorofuran-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, DMSO-d₆): δ_H 7.45 (1H, s), 7.19 (1H, d, J 3.0), 6.85 (2H, s), 6.67 (1H, d, J 3.0), 5.37 (2H, s), 4.28 (6H, br. s); MSm/z 333 (M + H).

Compound 58: 6-morpholin-4-ylmethyl-2-oxazol-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Oxazole-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, methanol-d₄) δ_H 8.10 (1H, s), 7.41 (1H, s), 7.35 (1H, s), 3.79 (2H, s), 3.68–3.73 (4H, m), 2.49–2.59 (4H, m); MSm/z 318 (M + H).

Compound 59: 6-((2,5-dihydro-1H-pyrrol-1-yl)methyl)-2-(oxazol-2-yl)thieno[2,3-d]pyrimidin-4-amine

Oxazole-2-carbonitrile was used in place of furan-2-carbonitrile. MSm/z 300 (M + H).

Compound 60: 6-((5,6-dihydropyridin-1(2H)-yl)methyl)-2-(oxazol-2-yl)thieno[2,3-d]pyrimidin-4-amine

Oxazole-2-carbonitrile was used in place of furan-2-carbonitrile. MSm/z 314 (M + H).

Compound 61: 6-morpholin-4-ylmethyl-2-thiazol-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Thiazole-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d): δ_H 7.99 (1H, d, J 3.2), 7.48 (1H, d, J 3.2), 7.03 (1H, s), 5.49 (2H, br. s), 3.66–3.80 (6H, m), 2.46–2.63 (6H, m); MSm/z 334 (M + H).

Compound 64: 2-isoxazol-3-yl-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Isoxazole-3-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, acetone-d₆): δ = 8.68 (1H, d, J 1.5), 7.33 (1H, s), 6.83–6.91 (3H, m), 3.66 (2H, s), 3.46–3.56 (4H, m), 2.31–2.43 (4H, m); MSm/z 318 (M + H).

Compound 65: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-isoxazol-3-yl-thieno[2,3-d]pyrimidin-4-ylamine

Isoxazole-3-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, acetone-d₆): δ_H 8.67 (1H, d, J 1.9), 7.30 (1H, s), 6.88 (1H, d, J 1.5), 6.82 (2H, br. s), 3.97 (2H, s), 2.33–2.51 (2H, m), 1.42–1.56 (2H, m), 1.10–1.26 (4H, m), 1.03 (6H, d, J 6.0); MSm/z 344 (M + H).

Compound 66: 6-pyrrolidin-1-ylmethyl-2-thiophen-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Thiophene-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.95 (1H, dd, J 3.7, 1.2), 7.41 (1H, dd, J 5.0, 1.2), 7.11 (2H, dd, J 5.0, 3.7), 5.33 (2H, br. s), 3.95 (2H, s), 2.71 (4H, br. s), 1.86 (4H, dt, J 6.7, 3.2); MSm/z 317 (M + H).

Compound 67: 6-morpholin-4-ylmethyl-2-thiophen-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Thiophene-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.95 (1H, dd, J 3.7, 1.2), 7.41 (1H, dd, J 5.0, 1.2), 7.12 (1H, dd, J 5.0, 3.7), 6.96 (1H, s), 5.18 (2H, br. s), 3.65–3.85 (6H, m), 2.47–2.65 (4H, m); MSm/z 333 (M + H).

Compound 68: 6-(2,5-dihydro-pyrrol-1-ylmethyl)-2-oxazol-4-yl-thieno[2,3-d]pyrimidin-4-ylamine

Oxazole-4-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, methanol-d₄) δ_H 8.51 (1H, s), 8.28 (1H, s), 7.34 (1H, s), 5.83 (2H, s), 4.13 (2H, s), 3.63 (4H, s); MSm/z 300 (M + H).

Compound 69: 6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-2-oxazol-4-yl-thieno[2,3-d]pyrimidin-4-ylamine

Oxazole-4-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.41 (1H, s), 7.98 (1H, s), 7.04 (1H, s), 5.74–5.83 (1H, m), 5.64–5.71 (1H, m), 5.44 (2H, br s), 3.85 (2H, s), 3.06–3.12 (2H, m), 2.65 (2H, t, J 5.7), 2.15–2.24 (2H, m); MSm/z 314 (M + H).

Compound 70: 2-benzofuran-2-yl-6-(4-fluoropiperdin-1-ylmethyl)thieno[2,3-d]pyrimidin-4-ylamine

Benzofuran-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.45–7.74 (3H, m), 7.30 (1H, m), 7.20 (1H, m), 6.94 (1H, br. s), 5.28 (2H, br. s), 4.66 (1H, d, J_HF 48.6), 4.46–4.67 (1H, m), 3.71 (2H, s), 2.38–2.66 (4H, m), 1.72–1.94 (4H, m); MSm/z 383 (M + H).

Compound 71: 6-(morpholinomethyl)-2-phenylthieno[2,3-d]pyrimidin-4-amine

Benzonitrile was used in place of furan-2-carbonitrile. MSm/z 327 (M + H).

Compound 72: 2-(3-fluoro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

3-Fluorobenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.24 (1H, d, J 7.9 Hz), 8.15 (1H, dt, J 10.5, 2.1), 7.44 (1H, td, J 8.0, 5.8), 7.07–7.22 (1H, m), 7.03 (1H, s), 5.23 (2H, br. s), 3.69–3.84 (6H, m), 2.51–2.63 (4H, m); MSm/z 345 (M + H).

Compound 73: 2-(3-chloro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

3-Chlorobenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.44 (1H, s), 8.31 (1H, dt, J 6.2, 2.2), 7.33–7.47 (2H, m), 6.99 (1H, s), 5.25 (2H, br. s), 3.67–3.85 (6H, m), 2.44–2.63 (4H, m); MSm/z 361 (M + H).

Compound 74: 2-(3,5-difluoro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

3,5-Difluorobenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.87–8.05 (2H, m), 7.00 (1H, s), 6.87 (1H, tt, J 8.7, 2.4), 5.23 (2H, br. s), 3.59–3.83 (6H, m), 2.41–2.67 (4H, m); MSm/z 363 (M + H).

Compound 75: 2-(3,4-difluoro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

3,4-Difluorobenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.28 (1H, ddd, J 11.9, 7.9, 2.1), 8.20 (1H, ddd, J 8.7, 4.5, 1.5), 7.15–7.25 (1H, m), 6.99 (1H, s), 5.19 (2H, br. s), 3.52–3.88 (6H, m), 2.46–2.62 (4H, m); MSm/z 363 (M + H).

Compound 76: 3-[4-amino-6-(2,5-dihydro-pyrrol-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, DMSO-d₆) δ_H 8.60–8.69 (2H, m), 7.91–7.99 (1H, m), 7.70 (1H, t, J 7.7), 7.60 (2H, br. s), 7.47 (1H, s), 5.83 (2H, s), 4.03 (2H, s), 3.52 (4H, s); MSm/z 334 (M + H).

Compound 77: 3-(4-amino-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-2-yl)-benzonitrile

Oxazole-2-carbonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.76 (1H, s), 8.67 (1H, dt, J 7.9, 1.5), 7.70 (1H, dt, J 7.8, 1.4), 7.55 (1H, t, J 7.9), 7.03 (1H, s), 5.34 (2H, br. s), 3.71–3.81 (6H, m), 2.51–2.63 (4H, m); MSm/z 352 (M + H). HRMS calcd for C₁₈H₁₇N₅OS 351.1154, found 352.1268 (M⁺ + H).

Compound 78: 3-[4-amino-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.77 (1H, s), 8.68 (1H, d, J 7.9), 7.70 (1H, d, J 7.9), 7.56 (1H, t, J 7.7), 7.00 (1H, s), 5.25 (2H, br. s), 3.74 (2H, d, J 2.3), 2.80–3.00 (2H, m), 1.93–2.15 (2H, m), 1.57–1.78 (2H, m), 1.19–1.39 (2H, m), 0.82–0.97 (6H, m); MSm/z 378 (M + H).

Compound 79: 3-[4-amino-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d) δ_H 8.77 (1H, s), 8.68 (1H, d, J 8.1), 7.70 (1H, dt, J 7.7, 1.3), 7.56 (1H, t, J 7.8), 7.00 (1H, s), 5.26 (2H, s), 4.73 (1H, d, J_HF 48.7), 3.78 (2H, s), 2.59–2.69 (2H, m), 2.48–2.58 (2H, m), 1.87–1.02 (4H, m); MSm/z 368 (M + H). HRMS calcd for C₁₉H₁₈FN₅S 367.1267, found 368.1301 (M⁺ + H).

Compound 80: 3-[4-amino-6-(3,3-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.77 (1H, t, J 1.5), 8.68 (1H, dt, J 7.9, 1.5), 7.70 (1H, dt, J 7.6, 1.5), 7.56 (1H, t, J 7.9), 7.04 (1H, s), 5.27 (2H, br. s), 3.89 (2H, s), 2.76 (2H, t, J_HF 11.1), 2.55–2.63 (2H, m), 1.77–1.99 (4H, m); MSm/z 386 (M + H).

Compound 81: 3-(4-amino-6-thiomorpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-2-yl)-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, methanol-d₄) δ_H 8.61–8.67 (2H, m), 7.93 (1H, ddd, J 7.7, 1.3, 1.1), 7.70 (1H, t, J 7.7), 7.60 (2H, br. s), 7.45 (1H, s), 3.78 (2H, s), 2.69–2.76 (4H, m), 2.61–2.67 (4H, m); MSm/z 368 (M + H).

Compound 82: 3-[4-amino-6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.75 (1H, t, J 1.5), 8.66 (1H, ddd, J 8.1, 1.3, 1.1), 7.69 (1H, ddd, J 7.7, 1.3, 1.1), 7.55 (1H, t, J 7.7), 7.06 (1H, s), 5.75–5.82 (1H, m), 5.64–5.71 (1H, m), 5.39 (2H, br. s), 3.86 (2H, s), 3.06–3.15 (2H, m), 2.67 (2H, t, J 5.7), 2.17–2.24 (2H, m); MSm/z 348 (M + H).

Compound 83: 3-(4-amino-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-2-yl)-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.76 (1H, s), 8.67 (1H, dt, J 7.9, 1.3), 7.69 (1H, dt, J 7.6, 1.5), 7.55 (1H, t, J 7.7), 7.03 (1H, s), 5.32 (2H, br. s), 3.90 (2H, s), 2.58–2.68 (4H, m), 1.77–1.89 (4H, m); MSm/z 336 (M + H).

Compound 84: 3-[4-amino-6-(2,6-dimethyl-morpholin-4-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,3-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, acetone-d₆): δ_H 8.54–8.65 (2H, m), 7.72 (1H, d, J 7.9), 7.57 (1H, t, J 8.1), 7.30 (1H, s), 6.84 (2H, br. s), 3.64 (2H, s), 3.42–3.58 (2H, m), 2.62–2.77 (2H, m), 1.63 (2H, t, J 10.7), 0.95 (3H, s), 0.93 (3H, s); MSm/z 380 (M + H).

Compound 85: 2-[4-amino-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,2-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d) δ_H 8.36 (1H, d, J 8.1), 7.81 (1H, d, J 7.6), 7.67 (1H, td, J 7.8, 1.3), 7.48–7.53 (1H, m), 7.05 (1H, s), 5.36 (2H, s), 4.74 (1H, d, J_HF 48.7), 3.79 (2H, s), 2.47–2.70 (4H, m), 1.83–2.02 (4H, m); MSm/z 368 (M + H).

Compound 86: 4-[4-amino-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,4-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.55 (2H, d, J 8.7), 7.74 (2H, d, J 8.7), 7.01 (1H, s), 5.25 (2H, s), 4.74 (1H, d, J_HF 48.6), 3.78 (2H, s), 2.48–2.69 (4H, m), 1.85–1.99 (4H, m); MSm/z 368 (M + H).

Compound 87: 4-[4-amino-6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,4-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.56 (2H, d, J 8.3), 7.74 (2H, d, J 8.3), 7.05 (1H, s), 5.76–5.84 (1H, m), 5.62–5.73 (1H, m), 5.22 (2H, br. s), 3.86 (2H, s), 3.08–3.13 (2H, m), 2.66 (2H, t, J 5.7), 2.17–2.24 (2H, m); MSm/z 348 (M + H).

Compound 88: 4-[4-amino-6-(2,5-dihydro-pyrrol-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

1,4-Dicyanobenzene was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.55 (2H, d, J 8.7), 7.74 (2H, d, J 8.7), 7.04 (1H, s), 5.81 (2H, s), 5.23 (2H, br. s), 4.09 (2H, s), 3.61 (4H, s); MSm/z 334 (M + H).

Compound 89: 6-((2,5-dihydro-1H-pyrrol-1-yl)methyl)-2-(3-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

3-(Trifluoromethyl)benzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.75 (1H, s), 8.65 (1H, d, J 7.9), 7.70 (1H, d, J 7.5), 7.59 (1H, t, J 7.9), 7.07 (1H, s), 5.83 (2H, s), 5.26 (2H, br. s), 4.11 (2H, s), 3.60–3.67 (4H, m). MSm/z 377 (M + H).

Compound 90: 6-((4-fluoropiperidin-1-yl)methyl)-2-(3-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

3-(Trifluoromethyl)benzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.75 (1H, s), 8.65 (1H, d, J 7.9), 7.70 (1H, d, J 7.9), 7.59 (1H, t, J 7.7), 7.04 (1H, s), 5.26 (2H, br. s), 3.81 (2H, s), 2.49–2.76 (4H, m), 1.88–2.04 (4H, m); MSm/z 411 (M + H).

Compound 91: 6-((4-fluoropiperidin-1-yl)methyl)-2-(4-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

4-(Trifluoromethyl)benzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 8.57 (2H, d, J 8.3), 7.72 (2H, d, J 8.3), 7.05 (1H, br. s), 5.26 (2H, br. s), 4.81 (1H, td, J 5.8, 3.0), 3.82 (2H, s), 3.37–3.67 (4H, m), 2.67 (4H, m); MSm/z 411 (M + H).

Compound 92: 6-((4-fluoropiperidin-1-yl)methyl)-2-(2-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

2-(Trifluoromethyl)benzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): v 7.79 (1H, d, J 7.9), 7.73 (1H, d, J 7.4), 7.64 (1H, t, J 7.3), 7.54 (1H, t, J 7.6), 7.06 (1H, s), 5.29 (2H, br. s), 4.74–4.90 (1H, m), 3.81 (2H, s), 3.35–3.70 (4H, m), 2.45–2.66 (4H, m); MSm/z 411 (M + H).

Compound 93: 6-((4-fluoropiperidin-1-yl)methyl)-2-(3-(methylsulfonyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

3-(Methylsulfonyl)benzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 9.04 (1H, s), 8.77 (1H, d, J 7.9), 8.03 (1H, d, J 7.5), 7.68 (1H, t, J 7.9), 7.07 (1H, br. s), 5.47 (2H, br. s), 4.76 (1H, d, J_HF 48.6), 3.81 (2H, br. s), 3.15 (3H, s), 2.60 (4H, m), 1.95 (4H, m); MSm/z 421 (M + H).

Compound 94: 6-((4-fluoropiperidin-1-yl)methyl)-2-(3-nitrophenyl)thieno[2,3-d]pyrimidin-4-amine

3-Nitrobenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d) δ_H 9.31 (1H, t, J 2.0), 8.79 (1H, dt, J 7.8, 1.3), 8.28 (1H, ddd, J 8.2, 2.3, 1.2), 7.62 (1H, t, J 7.9), 7.01 (1H, s), 5.25 (2H, s), 4.74 (1H, d, J_HF 48.7), 3.79 (2H, s), 2.48–2.69 (4H, m), 1.83–2.00 (4H, m); MSm/z 388 (M + H).

Compound 95: 3-(4-amino-6-((4-fluoropiperidin-1-yl)methyl)thieno[2,3-d]pyrimidin-2-yl)-N,N-dimethylbenzamide

3-Cyano-N,N-dimethylbenzamide was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.45 (1H, m), 8.41 (1H, dt, J 7.2, 1.9), 7.43–7.53 (2H, m), 7.31 (1H, s), 6.73 (2H, br. s), 4.71 (1H, d, J_HF 48.6), 3.76 (2H, s), 3.17 (3H, s), 3.08 (3H, s), 2.60–2.71 (2H, m), 2.45–2.57 (2H, m), 1.84–2.02 (4H, m). MSm/z 414 (M + H).

Compound 96: 6-(4-fluoro-piperidin-1-ylmethyl)-2-(3-methoxy-phenyl)-thieno[2,3-d]pyrimidin-4-ylamine

3-Methoxybenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 8.02 (1H, dt, J 7.6, 1.3), 7.99 (1H, dd, J 2.6, 1.5), 7.37 (1H, t, J 7.9), 6.96–7.02 (2H, m), 5.18 (2H, br. s), 4.72 (1H, d, J_HF 49.0), 3.92 (3H, s), 3.76 (2H, s), 2.59–2.69 (2H, m), 2.47–2.57 (2H, m), 1.85–1.99 (4H, m); MSm/z 373 (M + H).

Compound 97: 2-(3-methoxy-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

3-Methoxybenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 7.97–8.06 (2H, m), 7.37 (1H, t, J 7.9), 7.01 (1H, dd, J 2.6, 0.8), 6.98 (1H, s), 5.27 (2H, br. s), 3.91 (3H, s), 3.71–3.77 (6H, m), 2.52–2.57 (4H, m); MSm/z 357 (M + H).

Compound 98: 6-(3,3-difluoro-piperidin-1-ylmethyl)-2-(3-methoxy-phenyl)-thieno[2,3-d]pyrimidin-4-ylamine

3-Methoxybenzonitrile was used in place of furan-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d) δ_H 7.97–8.05 (2H, m), 7.37 (1H, t, J 8.1), 6.96–7.03 (2H, m), 5.32 (2H, s), 3.91 (3H, s), 3.85 (2H, s), 2.74 (2H, t, J_HF 11.1), 2.49–2.60 (2H, m), 1.73–1.98 (4H, m); MSm/z 391 (M + H).

Compounds 38–42 were prepared according to the procedures described for compound 18 except 5-difluoro-furan-2-carbonitrile was used in place of furan-2-carbonitrile. 5-Difluoro-furan-2-carbonitrile was prepared via the following procedure: To a solution of Et₂NSF₃ (2.8 mL, 21.4 mmol) and CH₂Cl₂ (10 mL) at 4 °C was added a solution of 5-formyl-furan-2-carbonitrile (2.44 g, 20.2 mmol; W. Hoyle and G. P. Roberts, J. Med. Chem., 1973, 16, 709) in CH₂Cl₂ (10 mL). After 30 min at 4 °C, saturated aqueous NaHCO₃ was added, the layers were separated and the aqueous layer was extracted with CH₂Cl₂. The combined organics were dried (Na₂SO₄) and concentrated to give 2.15 g of 5-difluoromethyl-furan-2-carbonitrile that was used without further purification.

Compound 38: 2-(5-difluoromethyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (400 MHz, DMSO-d₆) δ_H 7.63 (2H, br. s), 7.43 (1H, s), 7.19 (1H, d, J 3.4), 7.16 (1H, t, J 53.3), 7.02 (1H, m), 3.72 (2H, s), 3.59 (4H, t, J 4.4), 2.44 (4H, m); MSm/z 367 (M + H).

Compound 39: 2-(5-difluoromethyl-furan-2-yl)-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (400 MHz, acetone-d₆) δ_H 7.40 (1H, s), 7.19 (1H, d, J 3.4 Hz), 7.00 (1H, t, J 53.7 Hz), 6.93–6.97 (1H, m), 6.89 (1H, br. s), 4.08 (2H, s), 2.50–2.62 (2H, m), 1.53–1.67 (4H, m), 1.27–1.33 (2H, m), 1.15 (6H, d, J 6.4); MSm/z 393 (M + H).

Compound 40: 2-(5-difluoromethyl-furan-2-yl)-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (400 MHz, acetone-d₆) δ_H 7.39 (1H, s), 7.20 (1H, d, J 3.7), 7.01 (1H, t, J 53.7), 6.94–6.98 (1H, m), 6.89 (2H, br. s), 3.78 (2H, d, J 1.2), 2.61–2.71 (2H, m), 2.43–2.52 (2H, m), 2.08–2.10 (1H, m), 1.74–1.99 (4H, m); MSm/z 383 (M + H).

Compound 41: 2-(5-difluoromethyl-furan-2-yl)-6-(4,4-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (400 MHz, acetone-d₆) δ_H 7.41 (1H, s), 7.21 (1H, d, J 3.4), 7.01 (1H, t, J 53.7), 6.94–6.99 (1H, m), 6.92 (2H, br. s), 3.87 (2H, d, J 1.0), 2.66 (4H, t, J 5.5), 1.95–2.04 (4H, m); MSm/z 401 (M + H).

Compound 42: 2-(5-difluoromethyl-furan-2-yl)-6-(3,3-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (400 MHz, acetone-d₆) δ_H 7.41 (1H, s), 7.21 (1H, d, J 3.7), 7.01 (1H, t, J 53.7), 6.89–6.98 (3H, m), 3.90 (2H, s), 2.77 (2H, t, J 11.5), 2.58 (2H, t, J 5.0), 1.85–1.98 (2H, m), 1.71–1.81 (2H, m); MSm/z 401 (M + H).

Compound 63: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

Solid potassium-tert-butoxide (182 mg, 1.6 mmol) was added to a dioxane solution (4 mL) of 2-amino-3-cyanothiophene (1.0 g, 8.1 mmol) and 4-methyl-thiazole-2-carbonitrile (1.0 g, 8.1 mmol). The resulting mixture was heated in an oil bath at 130 °C for 10 minutes. The dark slurry was cooled to room temperature, diluted with THF, and dry packed onto silica gel. The material was the purified viacolumn chromatography to give 1.1 g of 2-(4-methylthiazol-2-yl)thieno[2,3-d]pyrimidin-4-amine.

Solid NBS (623 mg, 3.5 mmol) was added to a THF solution (30 mL) of 2-(4-methylthiazol-2-yl)thieno[2,3-d]pyrimidin-4-amine (800 mg, 3.2 mmol). After 3 h the mixture was diluted with EtOAc and washed with water and brine, dried (Na₂SO₄), and dry packed onto silica gel. Column chromatography gave 825 mg of 6-bromo-2-(4-methylthiazol-2-yl)thieno[2,3-d]pyrimidin-4-amine.

Neat vinylboronic acid dibutyl ester (1.0 mL, 4.7 mmol) was added to a dioxane (20 mL)/water (5 mL) solution of 6-bromo-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine (775 mg, 2.4 mmol), Pd(dppf)Cl₂ (196 mg, 0.2 mmol), and K₂CO₃ (650 mg, 4.7 mmol) and the mixture was heated to 80 °C. After 3 h the mixture was cooled and diluted with EtOAc. The organic phase was washed with water and brine, dried (Na₂SO₄) and dry packed onto silica gel. Column chromatography gave 460 mg of 2-(4-methyl-thiazol-2-yl)-6-vinyl-thieno[2,3-d]pyrimidin-4-ylamine.

Solid MeSO₂NH₂ (162 mg, 1.7 mmol) was added to a t-BuOH (8 mL)/water (8 mL) solution of AD mix-α (2.4 g). After 15 min the resulting mixture was added to an acetone suspension (8 mL) of 2-(4-methyl-thiazol-2-yl)-6-vinyl-thieno[2,3-d]pyrimidin-4-ylamine (460 mg, 1.7 mmol) and the mixture was stirred vigorously. After 18 h sodium sulfite (2.5 g) was added and the mixture was stirred for an additional 30 minutes. The mixture was extracted with EtOAc and the combined extracts were washed with water and brine, dried (Na₂SO₄), and concentrated to give 350 mg of 1-[4-amino-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidin-6-yl]-ethane-1,2-diol that was used without further purification.

Solid HIO₄ (775 mg, 3.4 mmol) was added to a THF solution (20 mL) of 1-[4-amino-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidin-6-yl]-ethane-1,2-diol (350 mg, 1.1 mmol). After 2 h saturated aqueous NaHCO₃ was added and the aqueous phase was extracted with EtOAc. The combined extracts were washed with water and brine, dried (Na₂SO₄), and dry packed onto silica gel. Column chromatography gave 113 mg of 4-amino-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidine-6-carbaldehyde.

Solid NaBH(OAc)₃ (45 mg, 0.21 mmol) was added to a THF solution (2 mL) of 4-amino-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidine-6-carbaldehyde (40 mg, 0.14 mmol) and cis-2,6-dimethyl-piperidine (58 μL, 0.43 mmol) and the mixture was heated to 45 °C. After 16 h the mixture was cooled, diluted with EtOAc, washed with saturated aqueous NaHCO₃, water and brine, dried (Na₂SO₄), and dry packed onto silica gel. Column chromatography gave 15 mg of 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine 63. ¹H NMR (Acetone, 300 MHz): δ = 7.29 (1H, s), 7.13 (1H, s), 6.87 (2H, br. s), 3.96 (2H, s), 2.43 (2H, br. s), 2.34 (3H, s), 1.38–1.58 (2H, m), 1.10–1.23 (4H, m), 1.02 (6H, d, J 6.4); MSm/z 374 (M + H).

The procedure used to prepare compound 63 was also used to prepare the following compounds with the appropriate amine substituent. Also, the corresponding nitrile replacement for the 4-methyl-thiazole-2-carbonitrile is specified where appropriate.

Compound 15: 2-(5-methyl-furan-2-yl)-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

5-Methylfuran-2-carbonitrile was used in place of 4-methyl-thiazole-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.17 (1H, d, J 3.4), 7.11 (1H, s), 6.15 (1H, d, J 3.4), 5.50 (2H, br. s), 3.94 (2H, s), 2.66–2.80 (4H, m), 2.44 (3H, s), 1.86 (4H, dt, J 6.4, 3.3); MSm/z 315 (M + H).

Compound 16: 2-(5-methyl-furan-2-yl)-6-piperidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

5-Methylfuran-2-carbonitrile was used in place of 4-methyl-thiazole-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d): δ_H 7.09 (1H, d, J 3.0), 6.90 (1H, s), 6.08 (1H, d, J 2.3), 5.21 (2H, br. s), 3.65 (2H, s), 2.42 (4H, br. s), 2.38 (3H, s), 1.55 (4H, quin, J 5.6), 1.39 (2H, d, J 5.1); MSm/z 329 (M + H).

Compound 19: 2-(5-methyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

5-Methylfuran-2-carbonitrile was used in place of 4-methyl-thiazole-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d): δ_H 7.17 (1H, d, J 3.3), 6.95 (1H, s), 6.15 (1H, d, J 2.5), 5.27 (2H, br. s), 3.61–3.80 (6H, m), 2.49–2.58 (4H, m), 2.45 (3H, s); MSm/z 331 (M + H).

Compound 20: 6-(3,4-dihydro-1H-isoquinolin-2-ylmethyl)-2-(5-methyl-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

5-Methylfuran-2-carbonitrile was used in place of 4-methyl-thiazole-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.06–7.23 (4H, m), 6.95–7.04 (2H, m), 6.14 (1H, dd, J 3.3, 0.8), 5.35 (2H, br. s), 3.91 (2H, s), 3.74 (2H, s), 2.91 (3H, t, J 5.3), 2.82 (2H, t, J 5.5); MSm/z 377 (M + H).

Compound 62: 2-(4-methyl-thiazol-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, acetone-d₆): δ_H 7.31 (1H, s), 7.13 (1H, s), 6.88 (2H, br. s), 3.65 (2H, s), 3.47–3.56 (4H, m), 2.35–2.40 (4H, m), 2.34 (3H, s); MSm/z 348 (M + H).

Compound 47: 2-(5-chloro-furan-2-yl)-6-(3,3-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Solid potassium-tert-butoxide (162 mg, 1.4 mmol) was added to a dioxane solution (4 mL) of 2-amino-5-methyl-thiophene-3-carbonitrile (1.0 g, 7.2 mmol) and 5-chlorofuran-2-carbonitrile (920 mg, 7.2 mmol). The resulting mixture was heated in an oil bath at 130 °C for 10 minutes. The dark slurry was cooled to room temperature, diluted with THF, and dry packed onto silica gel. The material was the purified viacolumn chromatography to give 950 mg of 2-(5-chloro-furan-2-yl)-6-methyl-thieno[2,3-d]pyrimidin-4-ylamine.

Solid DMAP (29 mg, 0.2 mmol) was added to a THF solution (12 mL) of (Boc)₂O (1.3 g, 5.9 mmol) and 2-(5-Chloro-furan-2-yl)-6-methyl-thieno[2,3-d]pyrimidin-4-ylamine (630 mg, 2.4 mmol). After 6 h the mixture was diluted with EtOAc and the organic layer was washed with water and brine, dried (Na₂SO₄), concentrated and purified viacolumn chromatography to give 928 mg of [2-(5-Chloro-furan-2-yl)-6-methyl-thieno[2,3-d]pyrimidin-4-yl]-bis-carbamic acid tert-butyl ester.

Solid benzoyl peroxide (34 mg, 0.1 mmol) was added to a benzene solution (10 mL) of DBDMH (314 mg, 1.1 mmol) and [2-(5-chloro-furan-2-yl)-6-methyl-thieno[2,3-d]pyrimidin-4-yl]-bis-carbamic acid tert-butyl ester (928 mg, 2.0 mmol) and the resulting mixture was heated to reflux. After 14 h the mixture was cooled to rt, diluted with EtOAc and the organic layer was washed with water and brine, dried (Na₂SO₄), concentrated and purified viacolumn chromatography to give 651 mg of [6-bromomethyl-2-(5-chloro-furan-2-yl)-thieno[2,3-d]pyrimidin-4-yl]-bis-carbamic acid tert-butyl ester.

Neat TFA (2 mL) was added to a CH₂Cl₂ solution (8 mL) of [6-bromomethyl-2-(5-chloro-furan-2-yl)-thieno[2,3-d]pyrimidin-4-yl]-bis-carbamic acid tert-butyl ester (651 mg). After 4 h saturated aqueous NaHCO₃ was added and the aqueous phase was extracted with EtOAc. The combined organics were washed with water and brine, dried (Na₂SO₄), and concentrated to give 369 mg of 6-bromomethyl-2-(5-chloro-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine that was used without further purification.

Solid 3,3-difluoro-piperidine hydrochloride (34 mg, 0.22 mmol) was added to a THF solution (1 mL) of diisopropylethyl amine (0.10 mL, 0.56 mmol) and 6-bromomethyl-2-(5-chloro-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine (50 mg, 0.14 mmol) and the mixture was heated to 40 °C. After 2 h the mixture was diluted with EtOAc then washed with water and brine, dried (Na₂SO₄), concentrated and purified viacolumn chromatography to give 31 mg of 2-(5-chloro-furan-2-yl)-6-(3,3-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine 47. ¹H NMR (chloroform-d, 300 MHz): δ = 7.23 (1H, d, J 3.4), 6.99 (1H, s), 6.34 (1H, d, J 3.4), 5.31 (2H, br. s), 3.86 (2H, s), 2.75 (2H, t, J 11.1), 2.57 (2H, t, J 5.1), 1.73–1.99 (4H, m); MSm/z 385 (M + H). HRMS calcd for C₁₈H₁₂ClF₂N₄OS 384.0623, found 385.0649 (M⁺ + H)

The procedure used to prepare compound 47 was also used to prepare the following compounds with the appropriate amine substituent:

Compound 45: 2-(5-chloro-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.23 (1H, d, J 3.8), 6.97 (1H, s), 6.34 (1H, d, J 3.8), 5.39 (2H, br. s), 3.68–3.80 (6H, m), 2.46–2.61 (4H, m); MSm/z 351 (M + H).

Compound 50: 2-(5-chloro-furan-2-yl)-6-(3,3-difluoro-pyrrolidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

¹H NMR (300 MHz, chloroform-d): δ_H 7.22–7.26 (1H, m), 7.00 (1H, s), 6.34 (1H, d, J 3.4 Hz), 5.41 (2H, br. s), 3.90 (2H, s), 3.01 (2H, t, J 13.2), 2.86 (1H, t, J 7.0), 2.33 (2H, tt, J 14.4, 7.1); MSm/z 371 (M + H).

Compound 51: 2-(5-bromo-furan-2-yl)-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

5-Bromofuran-2-carbonitrile was used in place of 5-chlorofuran-2-carbonitrile. ¹H NMR (300 MHz, chloroform-d): δ_H 7.20 (1H, d, J 3.4), 7.07 (1H, s), 6.47 (1H, d, J 3.6), 5.47 (2H, br. s), 3.91 (2H, s), 2.61–2.74 (4H, m), 1.85 (4H, dt, J 6.7, 3.2); MSm/z 380 (M + H).

Compound 52: 2-(5-bromo-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

5-Bromofuran-2-carbonitrile was used in place of 5-chlorofuran-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d): δ_H 7.20 (1H, d, J 3.4), 6.97 (1H, s), 6.48 (1H, d, J 3.4), 5.40 (2H, br. s), 3.61–3.86 (6H, m), 2.40–2.65 (4H, m); MSm/z 396 (M + H). HRMS calcd for C₁₅H₁₅BrN₄O₂S 394.0099, found 395.0147 (M⁺ + H).

Compound 53: 2-(5-bromo-furan-2-yl)-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

5-Bromofuran-2-carbonitrile was used in place of 5-chlorofuran-2-carbonitrile. ¹H NMR (400 MHz, chloroform-d): δ_H 7.19 (1H, d, J 3.4), 6.95 (1H, s), 6.48 (1H, d, J 3.7), 5.44 (2H, br. s), 4.11 (2H, s), 2.45–2.66 (2H, m), 1.55–1.70 (2H, m), 1.26–1.39 (4H, m), 1.19 (6H, d, J 6.1); MSm/z 422 (M + H).

Compound 32: 2-(5-ethyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

A 1 M THF solution of Et₂Zn (0.6 mL, 0.60 mmol) was added to a THF solution (1.5 mL) of Pd(dppf)Cl₂ (10 mg, 0.01 mmol) and 2-(5-bromo-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine 52 (60 mg, 0.15 mmol) and the mixture was refluxed. After 4 h the mixture was cooled and carefully diluted with EtOAc and water. The aqueous phase was extracted with EtOAc and the combined organics were washed with water and brine, dried (Na₂SO₄), and dry packed onto silica gel. Column chromatography gave 33 mg of the title compound. ¹H NMR (300 MHz, chloroform-d): δ_H 7.19 (1H, d, J 3.4), 6.95 (1H, s), 6.17 (1H, d, J 3.4), 5.32 (2H, s), 3.68–3.77 (6H, m), 2.81 (2H, q, J 7.5), 2.44–2.58 (4H, m), 1.25–1.34 (3H, m); MSm/z 345 (M + H).

The procedure to prepare compound 32 was also used to prepare the following compounds:

Compound 33: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-(5-ethyl-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 53 was used in place of compound 52. ¹H NMR (300 MHz, chloroform-d): δ_H 7.18 (1H, d, J 3.4), 6.95 (1H, s), 6.16 (1H, d, J 3.4), 5.34 (2H, br. s), 4.13 (2H, s), 2.81 (2H, q, J 7.4), 2.57 (2H, br. s), 1.78 (4H, br. s), 1.51–1.70 (2H, m), 1.23–1.35 (3H, m), 1.21 (6H, d, J 6.0); MSm/z 371 (M + H).

Compound 34: 2-(5-isopropyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

i-PrZnBr was used in place of Et₂Zn. ¹H NMR (400 MHz, chloroform-d): δ_H 7.18 (1H, d, J 3.4), 6.95 (1H, s), 6.15 (1H, d, J 3.4), 5.26 (2H, br. s), 3.68–3.79 (6H, m), 3.07–3.19 (1H, m), 2.45–2.59 (4H, m), 1.32 (6H, d, J 7.1); MSm/z 359 (M + H).

Compound 35: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-(5-isopropyl-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

i-PrZnBr and compound 53 were used in place of Et₂Zn and compound 52, respectively. ¹H NMR (300 MHz, chloroform-d): δ_H 7.17 (1H, d, J 3.4), 6.95 (1H, s), 6.14 (1H, d, J 3.0), 5.34 (2H, br. s), 4.13 (2H, s), 3.12 (1H, quin, J 6.9), 2.57 (2H, br. s), 1.51–1.80 (6H, m), 1.32 (6H, d, J 6.8), 1.2 (6H, d, J 6.0); MSm/z 385 (M + H).

Compound 37: 2-(5-cyclopropyl-furan-2-yl)-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Solid cyclopropylboronic acid (31 mg, 0.36 mmol) was added to a toluene (1 mL)/water (0.05 mL) suspension of 2-(5-bromo-furan-2-yl)-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine 53 (60 mg, 0.14 mmol), Pd(OAc)₂ (2 mg, 0.01 mmol), P(Cy)₃ (5 mg, 0.02 mmol) and K₃PO₄ (104 mg, 0.49 mmol) and the mixture was heated to 100 °C. After 4 h the mixture was cooled, diluted with EtOAc, washed with water and brine, dried (Na₂SO₄) and dry packed onto silica gel. Column chromatography gave 30 mg of 2-(5-cyclopropyl-furan-2-yl)-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine 37. ¹H NMR (300 MHz, chloroform-d): δ_H 7.15 (1H, d, J 3.4), 6.87–6.99 (1H, m), 6.03 (1H, d, J 3.0), 5.27 (2H, s), 4.12 (2H, s), 2.56 (2H, br. s), 2.00–2.11 (1H, m), 1.58–1.71 (2H, m), 1.23–1.41 (4H, m), 1.21 (3H, s), 1.19 (3H, s), 0.89–0.99 (2H, m), 0.79–0.88 (2H, m); MSm/z 383 (M + H).

Compound 36: 2-(5-cyclopropyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 36 was prepared according to the procedure described in compound 37 except compound 52 was used in place of compound 53. ¹H NMR (300 MHz, chloroform-d): δ_H 7.16 (1H, d, J 3.4), 6.95 (1H, s), 6.03 (1H, d, J 3.4), 5.29 (2H, s), 3.62–3.83 (6H, m), 2.47–2.56 (4H, m), 1.99–2.12 (1H, m), 0.90–1.00 (2H, m), 0.79–0.89 (2H, m); MSm/z 357 (M + H).

Adenosine A_2Areceptor functional assay. To initiate the functional assay, cryopreserved CHO-K1 cells overexpressing the human adenosine A_2Areceptor and containing a cAMP inducible β-galactosidase reporter gene were thawed, centrifuged, DMSO containing media removed, and then seeded with fresh culture media into clear 384-well tissue culture treated plates (BD #353961) at a concentration of 10 K cells per well. Prior to assay, these plates were cultured for two days at 37 °C, 5% CO₂ and 90% Rh. On the day of the functional assay, culture media was removed and replaced with 45 μL assay medium (Hams/F-12 Modified (Mediatech # 10-080CV) supplemented w/0.1% BSA). Test compounds were diluted and 11 point curves created at a 1000× concentration in 100% DMSO. Immediately after addition of assay media to the cell plates, 50 nL of the appropriate test compound antagonist or agonist control curves were added to cell plates using a Cartesian Hummingbird. Compound curves were allowed to incubate at room temperature on cell plates for approximately 15 minutes before addition of a 15 nM NECA (Sigma E2387) agonist challenge (5 μL volume). A control curve of NECA, a DMSO/media control, and a single dose of Forskolin (Sigma F3917) were also included on each plate. After additions, cell plates were allowed to incubate at 37 °C, 5% CO₂, 90% Rh for 5.5–6 hours. After incubation, media was removed, and cell plates were washed 1 × 50 μL with DPBS w/o Ca and Mg (Mediatech 21-031-CV). Into dry wells, 20 μL of 1× Reporter Lysis Buffer (Promega E3971 (diluted in dH₂O from 5× stock)) was added to each well and plates frozen at −20 °C overnight. For β-galactosidase enzyme colorimetric assay, plates were thawed out at room temperature and 20 μL 2× assay buffer (Promega) was added to each well. Color was allowed to develop at 37 °C, 5% CO₂, 90% Rh for 1–1.5 h or until reasonable signal appeared. The colorimetric reaction was stopped with the addition of 60 μL per well 1 M sodium carbonate. Plates were counted at 405 nm on a SpectraMax Microplate Reader (Molecular Devices). Data were analyzed in Microsoft Excel and IC/EC50 curves were fit using a standardized macro.

Adenosine A₁receptor functional assay. To initiate the functional assay, cryopreserved CHO-K1 cells overexpressing the human adenosine A₁receptor and containing a cAMP inducible β-galactosidase reporter gene were thawed, centrifuged, DMSO containing media removed, and then seeded with fresh culture media into clear 384-well tissue culture treated plates (BD #353961) at a concentration of 10 K cells per well. Prior to assay, these plates were cultured for two days at 37 °C, 5% CO₂ and 90% Rh. On the day of the functional assay, culture media was removed and replaced with 45 μL assay medium (Hams/F-12 Modified (Mediatech # 10-080CV) supplemented w/0.1% BSA). Test compounds were diluted and 11 point curves created at a 1000× concentration in 100% DMSO. Immediately after addition of assay media to the cell plates, 50 nL of the appropriate test compound antagonist or agonist control curves were added to cell plates using a Cartesian Hummingbird. Compound curves were allowed to incubate at room temperature on cell plates for approximately 15 minutes before addition of a 4 nM r-PIA (Sigma P4532)/1 μM Forskolin (Sigma F3917) agonist challenge (5 μL volume). A control curve of r-PIA in1 μM Forskolin, a DMSO/Media control, and a single dose of Forskolin were also included on each plate. After additions, cell plates were allowed to incubate at 37 °C, 5% CO₂, 90% Rh for 5.5–6 hours. After incubation, media was removed, and cell plates were washed 1 × 50 μL with DPBS w/o Ca and Mg (Mediatech 21-031-CV). Into dry wells, 20 μL of 1× Reporter Lysis Buffer (Promega E3971 (diluted in dH₂O from 5× stock)) was added to each well and plates frozen at −20 °C overnight. For β-galactosidase enzyme colorimetric assay, plates were thawed out at room temperature and 20 μL 2× assay buffer (Promega) was added to each well. Color was allowed to develop at 37 °C, 5% CO₂, 90% Rh for 1–1.5 h or until reasonable signal appeared. The colorimetric reaction was stopped with the addition of 60 μL per well 1 M sodium carbonate. Plates were counted at 405 nm on a SpectraMax Microplate Reader (Molecular Devices). Data were analyzed in Microsoft Excel and IC/EC50 curves were fit using a standardized macro.

Mouse catalepsy study. Haloperidol, a neuroleptic medication that inhibits dopamine D₂ receptors, was used to induce catalepsy. In the rodent, catalepsy is characterized by a loss of voluntary motion where limbs uncharacteristically remain in placed positions. Catalepsy was measured in haloperidol (1 mg kg⁻¹, s.c.) treated mice (fasted, male balb/c mice) after oral administration of compound (0.01, 0.10, 1.0, 3.0 or 10.0 mg kg⁻¹, p.o.), L-DOPA (300 mg kg⁻¹; co-administered with carbidopa (75 mg kg⁻¹)), or vehicle. Animals were randomly assigned to treatment groups and behavioral testing was performed blind to treatment. Control mice received the respective s.c. and p.o. vehicles. Haloperidol was dissolved in 0.3% tartaric acid in 0.9% saline. L-DOPA was diluted in 0.5% methylcellulose and dosed as a suspension. Compounds were diluted in 0.5% methylcellulose and dosed as a solution. Compounds were administered orally 30 min after haloperidol. Behavioral testing was conducted one hour after dosing of compounds. The behavioral test trial (maximum duration of 60 s) began by placing the forepaws of fasted, male balb/c mice (18–23 g) on a horizontal bar elevated 3.5 cm above the bench. The cataleptic state was regarded as over and the trial ended when the animal came off the bar by either placing its forepaws on the bench or climbing onto the bar with all of its limbs. Each value represents average (±SEM) time in cataleptic position of n = 9–11 mice per treatment group during a sixty s test session. Results are reported as an ED₅₀ or as active/not active at a single dose.

Notes and references

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Aminomethyl substituted thieno[2,3-d]pyrimidines as adenosine A2A receptor antagonists

Abstract

Introduction

Results and discussion

Conclusions

Experimental

Compound 18: 2-furan-2-yl-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 10: 6-dimethylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 11: 6-diethylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 12: 6-cyclopropylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 13: 6-cyclohexylaminomethyl-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 14: 2-furan-2-yl-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 17: 6-(azepan-1-ylmethyl)-2-(furan-2-yl)thieno[2,3-d]pyrimidin-4-amine

Compound 20: 6-(3,4-dihydro-1H-isoquinolin-2-ylmethyl)-2-(5-methyl-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 21: 6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 22: 6-(4-fluoro-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 23: 6-(4,4-difluoro-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 24: 6-(3,3-difluoro-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 25: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 26: 1-(4-amino-2-furan-2-yl-thieno[2,3-d]pyrimidin-6-ylmethyl)-piperidin-4-ol

Compound 27: 1-(4-amino-2-furan-2-yl-thieno[2,3-d]pyrimidin-6-ylmethyl)-piperidin-4-one

Compound 28: 2-(furan-2-yl)-6-(thiomorpholinomethyl)thieno[2,3-d]pyrimidin-4-amine

Compound 29: 6-((2,5-dihydro-1H-pyrrol-1-yl)methyl)-2-(furan-2-yl)thieno[2,3-d]pyrimidin-4-amine

Compound 30: 6-(3-fluoro-pyrrolidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 31: 6-(3,3-difluoro-pyrrolidin-1-ylmethyl)-2-furan-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 43: 2-(5-chloro-furan-2-yl)-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 44: 6-azepan-1-ylmethyl-2-(5-chloro-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 46: 2-(5-chloro-furan-2-yl)-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 48: 2-(5-chloro-furan-2-yl)-6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 49: 2-(5-chloro-furan-2-yl)-6-(2,5-dihydro-pyrrol-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 58: 6-morpholin-4-ylmethyl-2-oxazol-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 59: 6-((2,5-dihydro-1H-pyrrol-1-yl)methyl)-2-(oxazol-2-yl)thieno[2,3-d]pyrimidin-4-amine

Compound 60: 6-((5,6-dihydropyridin-1(2H)-yl)methyl)-2-(oxazol-2-yl)thieno[2,3-d]pyrimidin-4-amine

Compound 61: 6-morpholin-4-ylmethyl-2-thiazol-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 64: 2-isoxazol-3-yl-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 65: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-isoxazol-3-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 66: 6-pyrrolidin-1-ylmethyl-2-thiophen-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 67: 6-morpholin-4-ylmethyl-2-thiophen-2-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 68: 6-(2,5-dihydro-pyrrol-1-ylmethyl)-2-oxazol-4-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 69: 6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-2-oxazol-4-yl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 70: 2-benzofuran-2-yl-6-(4-fluoropiperdin-1-ylmethyl)thieno[2,3-d]pyrimidin-4-ylamine

Compound 71: 6-(morpholinomethyl)-2-phenylthieno[2,3-d]pyrimidin-4-amine

Compound 72: 2-(3-fluoro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 73: 2-(3-chloro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 74: 2-(3,5-difluoro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 75: 2-(3,4-difluoro-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 76: 3-[4-amino-6-(2,5-dihydro-pyrrol-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 77: 3-(4-amino-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-2-yl)-benzonitrile

Compound 78: 3-[4-amino-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 79: 3-[4-amino-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 80: 3-[4-amino-6-(3,3-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 81: 3-(4-amino-6-thiomorpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-2-yl)-benzonitrile

Compound 82: 3-[4-amino-6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 83: 3-(4-amino-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-2-yl)-benzonitrile

Compound 84: 3-[4-amino-6-(2,6-dimethyl-morpholin-4-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 85: 2-[4-amino-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 86: 4-[4-amino-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 87: 4-[4-amino-6-(3,6-dihydro-2H-pyridin-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 88: 4-[4-amino-6-(2,5-dihydro-pyrrol-1-ylmethyl)-thieno[2,3-d]pyrimidin-2-yl]-benzonitrile

Compound 89: 6-((2,5-dihydro-1H-pyrrol-1-yl)methyl)-2-(3-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

Compound 90: 6-((4-fluoropiperidin-1-yl)methyl)-2-(3-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

Compound 91: 6-((4-fluoropiperidin-1-yl)methyl)-2-(4-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

Compound 92: 6-((4-fluoropiperidin-1-yl)methyl)-2-(2-(trifluoromethyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

Compound 93: 6-((4-fluoropiperidin-1-yl)methyl)-2-(3-(methylsulfonyl)phenyl)thieno[2,3-d]pyrimidin-4-amine

Compound 94: 6-((4-fluoropiperidin-1-yl)methyl)-2-(3-nitrophenyl)thieno[2,3-d]pyrimidin-4-amine

Compound 95: 3-(4-amino-6-((4-fluoropiperidin-1-yl)methyl)thieno[2,3-d]pyrimidin-2-yl)-N,N-dimethylbenzamide

Compound 96: 6-(4-fluoro-piperidin-1-ylmethyl)-2-(3-methoxy-phenyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 97: 2-(3-methoxy-phenyl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 98: 6-(3,3-difluoro-piperidin-1-ylmethyl)-2-(3-methoxy-phenyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 38: 2-(5-difluoromethyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 39: 2-(5-difluoromethyl-furan-2-yl)-6-(2,6-dimethyl-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 40: 2-(5-difluoromethyl-furan-2-yl)-6-(4-fluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 41: 2-(5-difluoromethyl-furan-2-yl)-6-(4,4-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 42: 2-(5-difluoromethyl-furan-2-yl)-6-(3,3-difluoro-piperidin-1-ylmethyl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 63: 6-(2,6-dimethyl-piperidin-1-ylmethyl)-2-(4-methyl-thiazol-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 15: 2-(5-methyl-furan-2-yl)-6-pyrrolidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 16: 2-(5-methyl-furan-2-yl)-6-piperidin-1-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 19: 2-(5-methyl-furan-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Compound 20: 6-(3,4-dihydro-1H-isoquinolin-2-ylmethyl)-2-(5-methyl-furan-2-yl)-thieno[2,3-d]pyrimidin-4-ylamine

Compound 62: 2-(4-methyl-thiazol-2-yl)-6-morpholin-4-ylmethyl-thieno[2,3-d]pyrimidin-4-ylamine

Aminomethyl substituted thieno[2,3-d]pyrimidines as adenosine A_2A receptor antagonists