甲肟基团已成为多种 C-H 官能化的多功能导向基团。尽管甲肟作为一种强大的功能手柄很重要,但通常需要将甲肟转化为母酮,但通常需要苛刻且官能团不耐受的反应条件。因此,甲肟的应用及其随后在后期转化为相应的酮可能会出现问题。在这里,我们提出了一组替代条件,以使用光激发硝基芳烃实现甲肟到母酮的温和且官能团耐受的转化。该方法的实用性体现在其在头孢内酯 D 的全合成中的应用。此外,还提供了通过同位素标记研究以及反应副产物分析获得的这种转化的机制见解。
by one-pot reactions of ketone hydrazones with diselenium dibromide, which suggested the in situ formation of selone and diazoalkane intermediates. The thermolysis of these compounds gave symmetrical olefins, whereas oxidation afforded the corresponding azines. The reaction of acetophenone hydrazones with diselenium dibromide afforded 2,5-diarylselenophenes in moderate yields. The reaction proceeded
The compounds are cyclic acetals of 4'-(.alpha.-hydroxy-.alpha.-alkyl-p-tolyloxy)pivalophenones, e.g., ethylene glycol acetal of 4'-(.alpha.-hydroxy-.alpha.-heptadecyl-p-tolyloxy)pivalophenone, and are useful as anti-diabetic agents.
The reaction of pivalophenones with tetraphosphorus decasulfide afforded cis- and trans-3,5-di-tert-butyl-3,5-diaryl-1,2,4-trithiolanes, which equilibrated to give other isomers in refluxing toluene via thiopivalophenones and thiopivalophenone S-sulfides.
Polymyxin Derivates Useful As Antibacterial Agents
申请人:Magee Thomas Victor
公开号:US20120316105A1
公开(公告)日:2012-12-13
The present invention provides a new class of polymyxin derivates useful for treating bacterial infections, especially Gram-negative infections, that have reduced renal cytotoxicity.