Flavanone glycosides from Miconia trailii.

Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia trailii yielded two new flavanone glycosides, matteucinol 7-O-alpha-l-arabinopyranosyl(1-->6)-beta-d-glucopyranoside (miconioside A, 1) and farrerol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (miconioside B, 2), along with the known compounds matteucinol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (3), matteucinol (4), 2alpha,3beta,19alpha-trihydroxyolean-12-ene-24,28-dioic acid (bartogenic acid, 5), 2alpha,3beta,23-trihydroxyolean-12-ene-28-oic acid (arjunolic acid, 6), 2alpha,3alpha,19alpha, 23-tetrahydroxyurs-12-ene-28-oic acid (myrianthic acid, 7), and stigmast-4-ene-3,6-dione (8). The structures of 1-8 were elucidated by spectroscopic methods, including 2D NMR.

Natural products inhibiting Candida albicans secreted aspartic proteases from Lycopodium cernuum.

Activity-guided fractionation of an ethanol extract of Lycopodium cernuum for Candida albicans secreted aspartic proteases (SAP) inhibition resulted in the identification of six new (1-6) and four known (7-10) serratene triterpenes, along with the known apigenin-4'-O-(2' ',6' '-di-O-p-coumaroyl)-beta-D-glucopyranoside (11). On the basis of spectroscopic analysis, the structures of 1-10 were established as 3beta,14alpha,15alpha,21beta,29-pentahydroxyserratane-24-oic acid (lycernuic acid C, 1), 3beta,14alpha,15alpha,21beta-tetrahydroxyserratane-24-oic acid (lycernuic acid D, 2), 3beta,14beta,21beta-trihydroxyserratane-24-oic acid (lycernuic acid E, 3), 3beta,21beta,29-trihydroxy-16-oxoserrat-14-en-24-methyl ester (lycernuic ketone A, 4), 3alpha,21beta,29-trihydroxy-16-oxoserrat-14-en-24-methyl ester (lycernuic ketone B, 5), 3alpha,21beta,24-trihydroxyserrat-14-en-16-one (lycernuic ketone C, 6), 3beta,21beta-dihydroxyserrat-14-en-24-oic acid (lycernuic acid A, 7), 3beta,21beta,29-trihydroxyserrat-14-en-24-oic acid (lycernuic acid B, 8), serrat-14-en-3beta,21beta-diol (9), and serrat-14-en-3beta,21alpha-diol (10). The 13C NMR data for the known compounds 7 and 8 are reported for the first time. Compounds 1 and 11 showed inhibitory effects against C. albicans secreted aspartic proteases (SAP) with IC50 of 20 and 8.5 microg/mL, respectively, while the other compounds were inactive.

New sesquiterpenoids from the root of Guatteria multivenia.

A phytochemical investigation of the CHCl(3) fraction of an ethanol extract of the root of Guatteria multivenia furnished nine compounds, of which four are sesquiterpenes (1-4) and five are alkaloids (5-9). Of the four sesquiterpenes, two are new (1, 3), named guatterin A (1) and dihydromadolin-K (3), and two are known (2, 4), identified as madolin-K (2) and madolin-W (4). The five known alkaloids were identified as liriodenine (5), lysicamine (6), lanuginosine (7), guadiscine (8), and O-methylpallidine (9). All the known compounds were isolated from this species for the first time. Structures of the new compounds were determined by extensive NMR studies, including DEPT, COSY, HMQC, HMBC, and NOESY. Compound 7 showed weak inhibitory effect against Candida albicans secreted aspartic proteases (SAP) with IC(50) of 45 microg/mL. Compound 5 was found to have antimicrobial activity against C. albicans, Cryptococcusneoformans, Staphylococcus aureus, and methicillin-resistant S. aureus (MRS) with IC(50)/MIC values of 3.5/6.25, 2.0/12.5, 2.0/3.13, and 2.0/3.13 microg/mL, respectively.