Two new cembranoids from the leaves of Croton longissimus Airy Shaw.

Two new cembrane-type diterpenoids (1 and 2) along with five known compounds (3-7) were isolated from leaves of Croton longissimus collected in Thailand. Their structures were elucidated from spectroscopic evidence and compound 4 was found by HPLC analysis to be identical to oblongionoside B-a compound isolated from Croton oblongifolius-including the absolute configuration at the C-9 position.

Oblongionosides A-F, megastigmane glycosides from the leaves of Croton oblongifolius Roxburgh.

From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Croton oblongifolius Roxburgh, collected in Chiang Mai, Thailand, six megastigmane glycosides, named oblongionosides A-F were isolated together with eight known compounds, and their structures elucidated on the basis of spectroscopic data. Absolute structures were determined by HPLC analyses and application of the modified Mosher's method.

The unusual canangafruticosides A-E: five monoterpene glucosides, two monoterpenes and a monoterpene glucoside diester of the aryldihydronaphthalene lignan dicarboxylic acid from leaves of Cananga odorata var. fruticosa.

From the leaves of Cananga odorata var. fruticosa, five unusual monoterpene glucosides, named canangafruticosides A-E (1-5), along with two unusual non-glucosidic monoterpenes (6, 7) were isolated. An aryldihydronaphthalene-type lignan dicarboxylate (8) was also isolated, with two moles of canangafruticoside A (1) on its ester moiety. This lignan also showed strong blue fluorescence emission under basic conditions. The structures of these compounds were elucidated by means of spectroscopic methods, with their absolute configurations determined by application of the modified Mosher's method to a compound chemically derived from canangafruticoside E.

Megastigmane glucosides and an unusual monoterpene from the leaves of Cananga odorata var. odorata, and absolute structures of megastigmane glucosides isolated from C. odorata var. odorata and Breynia officinalis.

From a 1-BuOH-soluble fraction of a MeOH extract of Cananga odorata var. odorata, collected at the Botanical Garden of Chiang Mai University, a new megastigmane glucoside, named canangaionoside, and an irregular monoterpene were isolated. A known compound, breyniaionoside A, which has been obtained from the leaves of Breynia officinalis, was also isolated, and its absolute structure was substantiated for the first time in this study. On this occasion, the absolute stereochemistries of structurally related megastigmane glucosides, breyniaionosides B and C, isolated from B. officinalis were examined.