Two new auronols, amaronols A (1) and B (2), were isolated from the bark of Pseudolarix amabilis, along with pseudolaric acid B (3), pseudolaric acid C (4), demethoxydeacetoxy-pseudolaric acid B (5), pseudolaric acid B-beta-D-glucoside (6), pseudolaric acid A-beta-D-glucoside (7), and myricetin (8). The structures of amaronols A and B were established by spectral data interpretation as 2,4,6-trihydroxy-2-[(3',4',5'-trihydroxyphenyl) methyl]-3(2H)-benzofuranone and 2,4,6-trihydroxy-2-[(3', 5'-dihydroxy-4'-methoxyphenyl) methyl]-3(2H)-benzofuranone, respectively. Antimicrobial testing results of the eight compounds indicated that only pseudolaric acid B was active against Candida albicans (MIC, 3.125 microg/mL; MFC, 6.25 microg/mL), while myricetin was marginally active against Trichophyton mentagrophytes (MIC, 50 microg/mL).

Absolute Configuration, Conformation, and Chiral Properties of Flavanone-(3→8'')-Flavone Biflavonoids from Rheedia acuminata. -The title compounds (I) show considerable chiral stability. The absolute configuration and conformation are determined by circular dichroism, NMR, NOESY; and computational calculations. -(LI*, X.-C.; JOSHI, A. S.; TAN, B.; ELSOHLY, H. N.; WALKER, L. A.; ZJAWIONY,

Antifungal assay-guided isolation of the 95% ethanol extract of the stems of Colubrina retusa yielded jujubogenin 3-O-alpha-L-arabinofuranosyl(1-->2)-[beta-D-glucopyranosyl (1-->3)]-alpha-L-arabinopyranoside (1), which showed modest growth-inhibitory effects against Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus (MICs, 50 microg/mL). In addition, two new minor saponins, jujubogenin 3-O-alpha-L-arabinofuranosyl(1-->2)-[2-O-(trans, cis)p-coumaroyl-beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopy ranosi de (2), and jujubogenin 3-O-(5-O-malonyl)-alpha-L-arabinofuranosyl (1-->2)-[beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopyranoside (3), were obtained. Saponin 2 was marginally active against only C. neoformans, with a MIC of 50 microg/mL, while 3 was inactive. NMR spectroscopy was used extensively for the structure determination of these compounds. The previously reported ambiguity of the NMR assignments of jujubogenin saponins for carbons -26 to -29 was clarified by a comprehensive analysis of the NMR spectra of 1.

Furanonaphthoquinones, Atraric Acid and a Benzofuran from the Stem Barks of Newbouldia laevis. -5 Furonaphthoquinones (I)-(III) are isolated along with the rarely found atraric acid (IV) and the new benzofuran (V) from the stem barks of Newbouldia laevis. -(GORMANN, R.; KALOGA, M.; LI, X.-C.; FERREIRA, D.; BERGENTHAL, D.; KOLODZIEJ*, H.; Phytochemistry 64 (2003) 2, 583-587; Inst.

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