| 摘要 |
Prepn. of 1,3,5-thiadiazole-5-thiols of formula (I) comprises dehydrogenating 2,3-dihydro-1,3,4-thiadiazole-5-thiols of formula (II) or the corresp. tautomeric 1,3,4-thiadiazolidine-5-thiones: (where R is H, 1-4C alkyl, 7-8C aralkyl or 6-7C aryl, pref. Me).(I) are useful as intermediates for cephalosporin antibiotics. Process gives high yields (e.g. 75-85%) of high-purity products from readily preparable starting materials (US 3474108). In an example, (I, R = Me) is prepd. from (II, R = Me) by treating with K3/Fe(CN)6/.
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