ABSTRACT
Two pairs of rare benzofuran glucoside epimers, indicuses A and B and indicuses C and D, three biogenetically related compounds indicuses E-G, and one coumarin indicus H, as well as 11 known compounds, were isolated from the bark of Streblus indicus (Bur.) Corner. The structures of indicuses A-H were elucidated by NMR and MS data, as well as by CD. (S)-Marmesinin exhibited moderate antimicrobial activity in vitro against Bacillus subtilis and Saccharomyces cerevisiae. 7,8-Dihydroxy-3-(3-methyl-2-butenyl) coumarin, umbelliferone, and scopoletin displayed strong cytotoxic activity in vitro against human bladder carcinoma cell line EJ. The structure-activity relationships indicate that hydroxylation at C-7 in the cytotoxic compounds is crucial to their activities.
Subject(s)
Benzofurans/chemistry , Coumarins/chemistry , Glycosides/chemistry , Moraceae/chemistry , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Bacillus subtilis/drug effects , Benzofurans/isolation & purification , Cell Line, Tumor , Coumarins/isolation & purification , Furans/chemistry , Furans/isolation & purification , Glycosides/isolation & purification , Humans , Microbial Sensitivity Tests , Molecular Structure , Plant Bark/chemistry , Plant Extracts/chemistry , Saccharomyces cerevisiae/drug effects , Scopoletin/chemistry , Scopoletin/isolation & purification , Structure-Activity Relationship , Umbelliferones/chemistry , Umbelliferones/isolation & purificationABSTRACT
A pair of enantiomers and a pair of 2,3-dihydro-1H-indene epimers, rac-indidene A (rac-1), indidenes B and C (2, 3); four new coumarin glucosides (4-7); and four known coumarin glucosides (8-11) were isolated from the bark of Streblus indicus (Bur.) Corner. The structures of 1-11 were defined by physical data analyses, including MS, NMR, and single-crystal X-ray diffraction. The absolute configurations of the 2,3-dihydro-1H-indene derivatives were defined via experimental and calculated ECD data. rac-Indidene A and indidenes B and C showed inhibitory activity against A549 and MCF-7 tumor cells with IC50 values in the range of 2.2 ± 0.1 to 7.2 ± 0.9 µM.
