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From the seeds oiTephrosia villosa, a new prenylated dehydrorotenoid, identified as a 6a, 12a-dehydro-2,3,6-trimethoxy-8-(3',3'-dimethylallyl)-9,11-dihydroxyrotenone [1], has been isolated along with 12a-hydroxy-a-toxicarol (11-hydroxytephrosin) [2] and lupeol. Their structures were established on the basis of spectral evidence.

A facile procedure has been developed for the synthesis of 2-aryl/heteryl-4-(2H-l-benzopyran-2one-8-yl)-2,3-dihydro-l,5-benzothiazepines (5a-o) by the reaction of l-(2H-l-benzopyran-2-one-8-yl)-3aryl/heteryl-2-propenones (3a-k) with 2-aminothiophenols (4a,b) in toluene in the presence of triflouroacetic acid. All the compounds gave satisfactory elemental analysis

A novel synthesis of 2H,8H-benzo[1,2-b:3,4-b′]dipyran-2,8-diones, 2H,8H-benzo[1,2-b:5,4-b′]dipyran-2,8-diones, 2H-furo[2,3-h][1]benzopyran-2-ones, and 7H-furo[3,2-g][1]benzopyran-7-ones was achieved by developing 2-pyrone and furan ring over coumarin. 6- or 8-Ally-7-hydroxycoumarins on oxidation with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) afforded benzodipyrandiones and furobenzopyranones. The structures of the compounds now synthesized were established by analytical, spectral, and comparison with authentic samples prepared by the known procedures.