23536-59-6Relevant articles and documents
Diborane Reduction of Penicillins: Preparation of 7-Deoxopenicillanic Acid
Sammes, Peter G.,Smith, Steven,Woolley, Geoffrey T.
, p. 2603 - 2610 (2007/10/02)
The reduction of 6β-acylamidopenicillanates with diborane is shown to proceed by opening of the β-lactam ring to produce the corresponding amino alcohols.The chemistry of the reduction product from benzhydryl 6β-benzyloxycarbonylaminopenicillanate has been explored, in paticular its reaction with methanolic potassium hydroxide; no azetidines are formed.Cyclisation of the amino alcohol prepared from methyl penicillanate may be effected either indirectly, via the corresponding bromide, or directly, by use of a modified Mitsunobu reaction, to produce methyl 7-deoxypenicillanate.
Carbonic acid esters, and the preparation thereof and their use
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, (2008/06/13)
Carbonic acid esters of the formula substituent(s) substituents(s) wherein R'1 is lower alkyl which may have substituent)s) selected from the group of halogen, lower alkoxy and aryloxy, or ar(lower)-alkyl which may have substituents)s) selected from the group of lower alkoxy, halogen, nitro and cyano, and R'2 is benzotriazolyl which may have halogen; or a group represented by the formula: STR1 wherein Y' and Z' are each cyano, nitro, carbamoyl, esterified carboxy, lower alkanoyl, aroyl or disubstituted carbamoyl; provided that when R'2 is a group represented by the formula: STR2 wherein Y' and Z' are each cyano, nitro, carbamoyl or esterified carboxy, R'1 is ar(lower) alkyl having substituent(s) selected from the group of lower alkoxy, halogen, nitro and cyano. A process for the protection of amino and/or imino groups in compounds containing them by reacting them with the aforementioned esters is also disclosed.
