S.V. Bhat

Coumarins of Artemisia dracunculoides and 3',6-dimethoxy-4',5,7-trihydroxyflavone in A. arctica.

Abstract Six coumarins were isolated from Artemisia dracunculoides Pursh. Two of these are new, 7,8-methylenedioxy-6-methoxycoumarin and the γ,γ-dimethylallyl ether of scopoletin. The four others were scopoletin, scoparone, daphnetin methylene ether and daphnetin 7-methyl ether. Artemisia arctica Less. ssp. saxicola (Rydb.) Hulten yielded 3′,6-dimethoxy-4′,5,7-trihydroxyflavone.

Dihydroflavonols and other flavonoids of Eupatorium species

Abstract Chloroform extracts of a hybrid of Eupatorium capillifolium (Lam.) Small and E. perfoliatum L. yielded the dihydroflavonols (2R, 3R)-7-methoxy-3,5,4′-trihydroxyflavanone (IIa), (2R, 3R)-3,4′-dihydroxy-5,7-dimethoxyflavanone (IIIa) and either (2R, 3R)-3,7-dimethoxy-3,5,4′-trihydroxy- or (2R, 3R)-7,4′-dimethoxy-3,5,3′-trihydroxyflavanone (Ia or Ic). Ia (or Ic) and IIIa are new; the stereochemistry of IIa has not been assigned previously. Genkwanin and quercetin 3-methyl ether were also found. E. capillifolium gave IIIa and IIa. E. perfoliatum gave no crystalline flavone fractions.

Maculatin: An isomer of uvedalin epoxide from Polymnia maculata

The isolation of a new germacranolide, maculatin IIc or IId, from Polymnia maculata Cav. is reported.

Bahifolin, a new sesquiterpene lactone, and 5,7-dihydroxy-3,3′,4′,6-tetramethoxyflavone, a new flavone, from Bahia oppositifolia

Abstract Extraction of Bahia oppositifolia (Nutt.) DC. (Compositae) furnished a new sesquiterpene lactone bahifolin (I c) and the new flavone 5,7-dihydroxy-3,3′,4′6-tetramethoxyflavone (III a) whose structure was confirmed by synthesis from jaceidin (III e). Extraction of Bahia absinthifolia Benth. var. dealbata (Gray) Gray gave the known sesquiterpene lactones bahia I (I a) and bahia II (I b).

Sesquiterpene lactones and flavones of Iva frutescens

Abstract Extraction of Iva frutescens L. ssp. frutescens gave a new germacranolide frutescin, whose structure was established, and the flavone centaureidin (5,7,3′-trihydroxy-3,6,4′-trimethoxy-flavone). Iva frutescens L. ssp. oraria (Bartlett) Jackson furnished pectolinarigenin (5,7-dihydroxy-6,4′-dimethoxyflavone) and hispidulin (6-methoxy-5,7,4′-trihydroxyflavone).

Coumarin in amblyolepis setigera

Abstract Extraction of Amblyolepis setigera DC. furnished coumarin. No sesquiterpene lactones were isolated.