Reactions of benzyl 6-lsocyanopenicellanate with thiocarbonyl reagents. Novel rearrangements to 2,3-dihydrothiazolo [2,3-b][1,3]-thiazin -5-ones via penam C(5)–C(6) bond cleavage. X-Ray crystal structure and absolute configuration of two rearrangement products

Abstract

Base-promoted reactions of benzyl 6-isocyanopenicillanate with CS₂, with CS₂–Mel, and with PhNCS, Proceed via C(5)–C(6) bond cleavage to give pairs of diastereoisomers; the structures of two of these diastereoisomers were established by X-ray crystallography.