Constituents of leaves and their antimalarial and antifungal activity.

From the leaves of (an aquatic plant), one new compound, 24()-ethylcholest-6-ene-5α-ol-3--β-D-glucopyranoside (), along with 11 known metabolites (-), were isolated and identified by spectroscopic methods including 1D- and 2D NMR. Antifungal activity for ()-roemerine () (IC/MIC = 4.5/10 μg/mL against ) and antimalarial activity for ()-roemerine () and -methylasimilobine () (IC = 0.

New labdane diterpenes from Leonurus cardiaca.

Leonurus cardiaca L. has been used in oriental medicine against several types of disorders. The ethanolic extract of leaves of Leonurus cardiaca yielded three new labdane-type diterpenes: 15- O-ethylleopersin C (1), 15- O-methylleopersin C (2), and 15- EPI- O-methylleopersin C (3).

Antioxidant constituents of Nymphaea caerulea flowers.

As part of an ongoing search for antioxidants from medicinal plants, 20 constituents were isolated from the Nymphaea caerulea flowers, including two 2S,3S,4S-trihydroxypentanoic acid (1), and myricetin 3-O-(3''-O-acetyl)-alpha-L-rhamnoside (2), along with the known myricetin 3-O-alpha-L-rhamnoside (3), myricetin 3-O-beta-D-glucoside (4), quercetin 3-O-(3''-O-acetyl)-alpha-L-rhamnoside (5), quercetin 3-O-alpha-L-rhamnoside (6), quercetin 3-O-beta-D-glucoside (7), kaempferol 3-O-(3''-O-acetyl)-alpha-L-rhamnoside (8), kaempferol 3-O-beta-D-glucoside (9), naringenin (10), (S)-naringenin 5-O-beta-D-glucoside (11), isosalipurposide (12), beta-sitosterol (13), beta-sitosterol palmitate (14), 24-methylenecholesterol palmitate (15), 4alpha-methyl-5alpha-ergosta-7,24(28)-diene-3beta,4beta-diol (16), ethyl gallate (17), gallic acid (18), p-coumaric acid (19), and 4-methoxybenzoic acid (20). The structures were determined by spectroscopic means. Compounds were tested for antioxidant activity and nine compounds 2-7, 11, 12 and 18 were considered active with IC(50) of 1.

Potent in vitro antifungal activities of naturally occurring acetylenic acids.

Our continuing effort in antifungal natural product discovery has led to the identification of five 6-acetylenic acids with chain lengths from C(16) to C(20): 6-hexadecynoic acid (compound 1), 6-heptadecynoic acid (compound 2), 6-octadecynoic acid (compound 3), 6-nonadecynoic acid (compound 4), and 6-icosynoic acid (compound 5) from the plant Sommera sabiceoides. Compounds 2 and 5 represent newly isolated fatty acids. The five acetylenic acids were evaluated for their in vitro antifungal activities against Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Candida parapsilosis, Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Trichophyton mentagrophytes, and Trichophyton rubrum by comparison with the positive control drugs amphotericin B, fluconazole, ketoconazole, caspofungin, terbinafine, and undecylenic acid.

Aromatic constituents of Uvaria grandiflora.

Grandiuvarone A (1) and grandiuvarins A-C (2-4) were isolated from the bark of Uvaria grandiflora. The structures of these new aromatic compounds were elucidated on the basis of spectroscopic analyses, especially 2D NMR techniques. Only compound 1 exhibited antileishmanial activity, with IC(50)/IC(90) values of 0.