Five new rifamycin derivatives, named salinirifamycins A-E (1-5), were isolated from a Brazilian marine Salinispora arenicola (BRA-213) strain extract. The structures of the new rifamycins were elucidated using a combination of NMR, IR, UV, and MS spectroscopic techniques, quantum-chemical calculations (DFT-calculated 13C NMR chemical shifts and DP4+ probability analysis), and comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1, 2, and 4 displayed antibacterial activity against Staphylococcus aureus and Enterococcus faecalis with MIC values ranging from 2.0 to 125.0 μg/mL, whereas 5 exhibited an MIC of 0.02 μg/mL to S. aureus, similar to the positive control rifampicin (MIC 0.03 μg/mL).
Salinirifamycins A–E: Rifamycin S Derivatives from the Brazilian Marine Actinomycete Salinispora arenicola / Batista Da Silva, A., Pinto, F.C.L., Silveira, E.R., Paulo, T.D.F., Wilke, D.V., Ferreira, E.G., Costa-Lotufo, L.V., Canuto, K.M., Marinho-Filho, J.D.B., Barros, A.B., Nuzzo, G., Fontana, A., Monteiro, N.Kássio.V., Pessoa, O.D.L.. - In: JOURNAL OF NATURAL PRODUCTS. - ISSN 0163-3864. - 89:1(2026), pp. 304-312. [10.1021/acs.jnatprod.5c01381]
Salinirifamycins A–E: Rifamycin S Derivatives from the Brazilian Marine Actinomycete Salinispora arenicola
Fontana, Angelo;
2026
Abstract
Five new rifamycin derivatives, named salinirifamycins A-E (1-5), were isolated from a Brazilian marine Salinispora arenicola (BRA-213) strain extract. The structures of the new rifamycins were elucidated using a combination of NMR, IR, UV, and MS spectroscopic techniques, quantum-chemical calculations (DFT-calculated 13C NMR chemical shifts and DP4+ probability analysis), and comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1, 2, and 4 displayed antibacterial activity against Staphylococcus aureus and Enterococcus faecalis with MIC values ranging from 2.0 to 125.0 μg/mL, whereas 5 exhibited an MIC of 0.02 μg/mL to S. aureus, similar to the positive control rifampicin (MIC 0.03 μg/mL).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
