RESUMO
The thiazorifamycins are derived from rifamycin S and cysteine; rifamycins P and Verde are formed by chemical reactions, while rifamycin Q synthesis involves obligatory enzymatic assistance. All antibiotics come from a common six-member precursor lacking C-1 of cysteine; the thiazin-2-one ring of rifamycin Verde retains both C-2 and C-3 of cysteine, while the thiazole ring of rifamycins P and Q retains only C-2, C-3 becoming exocyclic in the ring-contraction C-3 is present in rifamycin Q but not in P.
Assuntos
Nocardia/metabolismo , Rifamicinas/biossíntese , Biotransformação , Fenômenos Químicos , Química , Mutação , Nocardia/genéticaRESUMO
Rifamycin R is a novel ansamycin produced by a mutant of Nocardia mediterranea; both physical and chemical data indicate that it is 30-demethyl-30-hydroxymethyl rifamycin S.
Assuntos
Nocardia/metabolismo , Rifamicinas/isolamento & purificação , Fenômenos Químicos , Química , Espectroscopia de Ressonância Magnética , Mutação , Rifamicinas/biossíntese , Espectrofotometria InfravermelhoRESUMO
The synthesis of some dimeric hydrazones of 3-formylrifamycin SV is described. The chemical and physical characteristics, the antibacterial activity and other biolgoical properties of the new derivatives are reported.
