Abstract
Neo-actinomycins A and B (1 and 2), two new natural actinomycins featuring an unprecedented tetracyclic 5H-oxazolo[4,5-b]phenoxazine chromophore, were isolated from the marine-derived actinomycete Streptomyces sp. IMB094. Their structures were elucidated by spectroscopic analyses. The presence of this ring system was proposed to originate from a condensation between actinomycin D (3) with α-ketoglutarate and pyruvate, respectively. Compound 1 showed potent cytotoxic activities against human cancer HCT116 and A549 cell lines in the nanomolar range (IC50: 38.7 and 65.8 nM, respectively) and moderate antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) strains.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Anti-Bacterial Agents / chemistry
-
Anti-Bacterial Agents / isolation & purification*
-
Anti-Bacterial Agents / pharmacology
-
Antibiotics, Antineoplastic / chemistry
-
Antibiotics, Antineoplastic / isolation & purification*
-
Antibiotics, Antineoplastic / pharmacology
-
Aquatic Organisms / chemistry*
-
Aquatic Organisms / isolation & purification
-
Biological Products / chemistry
-
Biological Products / isolation & purification*
-
Biological Products / pharmacology
-
Cell Line, Tumor
-
Cell Survival / drug effects
-
Dactinomycin / chemistry
-
Dactinomycin / isolation & purification*
-
Dactinomycin / pharmacology
-
Enterococcus / drug effects
-
Humans
-
Inhibitory Concentration 50
-
Molecular Structure
-
Spectrum Analysis
-
Staphylococcus aureus / drug effects
-
Streptomyces / chemistry*
-
Streptomyces / isolation & purification
Substances
-
Anti-Bacterial Agents
-
Antibiotics, Antineoplastic
-
Biological Products
-
Dactinomycin