title: Modifications of a macrolide antibiotic midecamycin. II. Reaction of midecamycin and 9-acetylmidecamycin with dimethylsulfoxide and acetic anhydride.
abstract: Treatment of 9,2'-diacetylmidecamycin (2) with DMSO and acetic anhydride afforded 3''-methylthiomethyl derivative (3) preferably in the presence of pyridine. Reaction of midecamycin (1) with DMSO and acetic anhydride gave 2'-acetyl-9-dehydro-3''-methylthiomethyl derivative (9) indicating that the three hydroxyl groups reacted in a different way to the reagent. When compound 2 was reacted with DMSO and acetic anhydride in the presence of CCl4, 3''-acetoxymethyl derivative (13) was a major product, which was formed via 3 through the Pummerer rearrangement. The structures of 3, 9 and 13 were confirmed by examining NMR and mass spectra of these compounds and their deuterio analogue. They showed antimicrobial spectra similar to 1 but superior in vivo activity.
mesh_terms: D000089:Acetic Anhydrides; D000900:Anti-Bacterial Agents / Q000031:analogs & derivatives / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D004121:Dimethyl Sulfoxide; D006868:Hydrolysis; D007933:Leucomycins / Q000031:analogs & derivatives / Q000494:pharmacology; D009174:Mycoplasma / Q000187:drug effects; D010084:Oxidation-Reduction; D013211:Staphylococcus aureus / Q000187:drug effects; D015645:Tylosin / Q000031:analogs & derivatives*
chemical_list: D000089:Acetic Anhydrides; D000900:Anti-Bacterial Agents; D007933:Leucomycins; C024643:9-acetylmidecamycin; C026483:midecamycin; D015645:Tylosin; D004121:Dimethyl Sulfoxide