Mohammad Ilyas

Luteolin 3′-xylosyl(1→2) glucoside from viburnum grandifolium

Abstract A novel flavone glycoside, luteolin 3′-O-β-xylosyl(1→2) glucoside, together with apigenin 7-xylosyl(1→2) glucoside has been isolated from V. grandifolium. The structure were elucidated by means of 1HNMR, 13CNMR, IR, UV and NOE spectral data.

A novel chalcone from Garcinia nervosa

A novel chalcone 5′-bromo-2′-hydroxy-4,4′,6′-trimethoxy-chalcone, isoliquiritigenin-4,4′-dimethyl ether (2′-hydroxy-4,4′-dimethoxy chalcone) and 2′-hydroxy-3,4,4′,6′-tetramethoxy dihydrochalcone have been isolated from the leaves of Garcinia nervosa. Their structure have been elucidated on the basis of chemical and spectral evidences (1H NMR, 13C NMR, HMQC, NOE, IR, UV and mass spectra).

Biomimetic synthesis of some novel coumarin dimers

Abstract 7,7′-dimethoxy-4,4′-dimethyl -3,3′-bicoumarin; 7,7′-dimethoxy-4,4′-dimethyl-3,6′-bicoumarin; 7,7′,8,8′-tetramethoxy-4,4′-dimethyl-3,3′-bicoumarin and 7,7′,8,8′-tetramethoxy-4,4′-dimethyl-3,5′-bicoumarin have been synthesized by the oxidation of 7-methoxy-4-methylcoumarin and 7,8-dimethoxy-4-methylcoumarin with Mn(OAc) 3 HClO 4 respectively.

Taiwaniaflavone and its derivatives: a new series of biflavones from Taiwania cryptomerioides Hayata

Taiwaniaflavone (3,3′-linked biapigenin)(1) and its methyl ethers [(2) and (3)] isolated from the leaves of Taiwania cryptomerioides Hayata (Taxodiaceae) have been identified on the basis of spectral data and by synthesis of taiwaniaflavone methyl ethers [(5) and (29)]. Five known biflavones [(7), (8), (9), (10), and (11)] have also been isolated from the same plant.

A new chromone from Cassia nodosa

A new chromone named as 5,4′-dihydroxy-7-methyl 3-benzyl chromone (1) along with three known flavonoid compounds as unsubstituted flavone, kaempferol-3-o-rhamnoside and quercetin-3-o-arabinoside have been isolated from the leaves of Cassia nodosa. Their structures have been established by means of chemical and spectral evidences (IR, UV, 1H-NMR, 13C-NMR and mass spectra).