Prepn. of orally administrable antibiotics - which are alpha amino penicillanic and cephalosporanic acid amide(s)

摘要

Beta lactams of formula (I) (where R=H or OH; B is C(CH3)2 or CH2CH2C(CH2R3)C R1=H, alkyl or phthalidyl; R3=H, halogen, OCOCH3 or -SR4;R4=5- or 6-membered heterocycle contg. 1-4 O,N, or S heteroatoms and which may be opt. substd. by 1-4C alkyl, lower cycloalkyl, alkenyl, amino, substd amino, or halogen), are prepared by reaction of an amino acid (II) with a diacid (III) or a reactive derivative of (III)(where A is -(CH2)n- or an arylene group; n= 0 or 1-4) to give a cpd. of formula (IV). The carboxyl groups in (IV) may then be esterified to introduce groups R1, and the intermediate (IV) is hydrolysed with acid to give (I). Cpds. are antibiotics which may be given orally.