| 摘要 |
Title compds. I(R = H , C1-4 lower alkyl; R1 = H, OH; M = H or inorg. base such as Na, K, & Ca, or C1-4 alkylamine), intermediates for manufg. penicillin or cephalosporin, were prepd. by the reaction of VIII (R2 = NHCOC1 or N=C=O) and X. silane and by reacting phosgene or trichloromethylchlorocarbonate. Compds. X were prepd. by activating II with trimethylchlorosilane. Thus, a mixt. of D-phenylglycine, methylene chloride, triethylamine, and trimethylchlorosilane was mixed with 1-ethyl-2,3-dioxopiperazine, and phosgene added to give I(alkyl group is ethyl).
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