Three new epoxyfuranoid lignans, 4alpha,5alpha-epoxybeilschmin A (1), 4alpha,5alpha-epoxybeilschmin B (2), and beilschmin D (3), together with nine known compounds have been isolated from the leaves of Beilschmiedia tsangii. The structures of these new compounds were determined through spectral analyses. Among the isolates, beilschmin A (4) and beilschmin B (5) exhibited potent antitubercular activities (MICs = 2.5 and 7.5 microg/mL, respectively) against Mycobacterium tuberculosis 90 - 221387 in vitro.

A new benzopyran, (S)-3-hydroxygarcibenzopyran, and three new biphenyls, garcibiphenyl C, garcibiphenyl D, garcibiphenyl E, together with thirteen known compounds have been additionally isolated from the root of Garcinia linii. The structures of these new compounds were determined through spectral analyses. Among the isolates, 1,7-dihydroxy-3-methoxyxanthone and 1,5-dihydroxy-3-methoxyxanthone showed antitubercular activities with MICs of 3.1 +/- 0.5 and 6.3 +/- 1.0 microg/mL against Mycobacterium tuberculosis 90-221,387 in vitro, respectively.

Two new flavones, 8-hydroxy-7,3¢,4¢,5¢-tetramethoxyflavone and 8,4¢-dihydroxy-7,3¢,5¢-trimethoxyflavone, together with thirteen known compounds have been isolated from the stem bark of Muntingia calabura. The structures of two new compounds were determined through spectral analyses. Among the isolates, 8-hydroxy-7,3¢,4¢,5¢-tetramethoxyflavone, 8,4¢-dihydroxy-7,3¢,5¢-trimethoxyflavone, and 3-hydroxy-1-(3,5-dimethoxy-4-hydroxyphenyl)propan-1-one exhibited effective cytotoxicities (ED 50 values = 3.56, 3.71, and 3.27 mg/mL, respectively) against the P-388 cell line in vitro.

A new pyridone alkaloid, 5,6-dihydro-5-hydroxy-1H-pyridin-2-one (1), and a new ester, sintenin ( 3-(3,4-dimethoxyphenyl)propyl 3-(3,4-dimethoxyphenyl)propanoate 2), together with three known compounds, 5,6-dihydro-1H-pyridin-2-one (3), d-sesamin ( 5,5'-(3a,4,6,6a-tetrahydro-1H,3H-furo[3,4-c]furan-1,4-diyl)bis[1,3-benzodioxole]; 4), and (E)-phytol ( 3,7,11,15-tetramethylhexadec-2-en-1-ol; 5) have been isolated from the whole plant of Piper sintenense. The structures of the two new compounds were determined through spectral analyses. Among twenty isolates obtained so far, four compounds exhibited effective cytotoxicities against P-388, HT-29, or A549 cell lines in vitro.

Two new esters, methyl 4-(prenyloxy)dihydrocinnamate and methyl 4-(geranyloxy)dihydrocinnamate, together with fourteen known compounds have been isolated from the stem bark of Zanthoxylum pistaciiflorum. The structures of two new compounds were determined through spectral analyses. Among the isolates, four compounds exhibited effective cytotoxicities against P-388 and HT-29 cell lines in vitro.