Antifungal Enantiomeric Styrylpyrones from Sanrafaelia ruffonammari and Ophrypetalum odoratum.

Phytochemical investigation of Sanrafaelia ruffonammari Verd and Ophrypetalum odoratum Diels that belongs to the rare genera confined to East African coastal forests led to the isolation of enantiomeric styrylpyrone dimer, (±)-5-methoxy-7-phenyl-[4-methoxy-2-pyronyl]-1-(E)-styryl-2-oxabicyclo-[4.2.0]-octa-4-en-3-one (1) alongside (+)-6-styryl-7,8-epoxy-4-methoxypyran-2-one (2) and the enantiomeric (+)- (3) and (-)-6-styryl-7,8-dihydroxy-4-methoxypyran-2-ones (4).

Morroniside cinnamic acid conjugate as an anti-inflammatory agent.

A morroniside cinnamic acid conjugate was prepared and evaluated on E-selectin mediated cell-cell adhesion as an important role in inflammatory processes. 7-O-Cinnamoylmorroniside exhibited excellent anti-inflammatory activity (IC(50)=49.3 microM) by inhibiting the expression of E-selectin; further, it was more active than another cinnamic-acid-conjugated iridoid glycoside (harpagoside; IC(50)=88.

Phenolic and bis-iridoid glycosides from Strychnos cocculoides.

A new bis-iridoid glucoside, cocculoside (1), has been isolated, together with five known compounds from Strychnos cocculoides (Loganiaceae), collected in Tanzania. The structure of cocculoside (1) has been determined as an ester dimer of loganin and secologanin dimethyl acetal between C-7 and C-11.

Iodine-catalyzed etherification of morroniside.

In this study, we describe a highly selective etherification procedure of unprotected morroniside catalyzed by molecular iodine in acetone. The etherification reaction furnished 7-O-alkyl ether derivatives in reasonable yields within few hours under neutral conditions. Studies of the obtained products on cytotoxicity activity in colon 26-L5 cell line were examined.

Synthesis of 2(R),3-dihydroxypropyl and 2(R),3(R)-dihydroxybutyl beta-D-fructopyranosides and some derivatives.

The synthesis of 2(R),3-dihydroxypropyl and 2(R),3(R)-dihydroxybutyl beta-d-fructopyranosides, and some derivatives, employing Sharpless-type catalytic asymmetric dihydroxylation procedures is described. Some aspects of the reactions, including stereoselectivities and chemical evidence for the assigned stereochemistry of the main products are reported.