91530-80-2Relevant academic research and scientific papers
Stereospecific Synthesis of Some Novel cis-1-Aza Analogs of Cepham
Sharma, S. D.,Arora, S. K.,Mehra, Usha
, p. 895 - 901 (2007/10/02)
Annelation of N-acyl-2-thiomethyltetrahydropyrimidines (VII) with appropriate acid chlorides results in the formation of the corresponding β-methylthio-β-lactam (VIII) as single stereoisomer in each case.Treatment of these β-methylthio-β-lactams (VIII) with Ni in acetone yields stereospecifically the cis-1-azacepham analogs (IX).Application of a similar sequence of reactions on VIIf furnishes the novel 1-azacepham analog (XI) through a single step removal of the thiomethyl as well as the benzyloxycarbonyl groups from the intermediate β-lactam (X).Potassium carbethoxyacetonylglycinate (B) on treatment with the schiff base VIIa using POCl3/Et3N in CH2Cl2 gives the enamino-β-lactam (XII) which on exposure to HCl in ethanol yields the α-amino-β-lactam (XIV).Acylation of XIV with phenoxyacetyl chloride provides the α-amido-β-methylthio-β-lactam (XV).Raney-Ni desulphurisation of XII and XV affords ths cis-azacephams XIII and XVI respectively.
