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(Diacetoxyiodo)benzene in the presence of acetic–trifluoroacetic acid in THF has been developed for the chemoselective para-methoxybenzylic C H bond oxidation to provide aryl carbonyl compounds at room temperature. The reaction condition is also applicable for the chemoselective deprotection of para-methoxybenzyl (PMB) ether in the presence of benzyl ether.

The n-BuOH-soluble portion of the 95% EtOH extract of red fermented rice fermented with the yellow mutant of the fungus Monascus purpureus BCRC 38113 (Monascaceae) led to the isolation of one new pyran-2-one derivative, namely peroxymonascuspyrone (1), along with nine known compounds, monasfluore A (2), monasfluore B (3), 3-epi-betulinic acid (4), 3-epi-betulinic acid acetate (5), alpha-tocospiro A (6), friedelan-3-one (7), alpha-cadinol (8), anticopalol (9), and spathulenol (10). Interestingly, this is the first report of a naturally occurring pyran-2-one skeleton isolated from Monascus sp. Their structures and relative configurations were elucidated by spectroscopic methods, including 1D- and 2D-NMR ((1)H,(1)H-COSY, HMQC, HMBC and NOESY), as well as low- and high-resolution mass spectrometric analyses. In addition, cytotoxicities against MCF-7, NCI-H460 and SF-268 cancer cell lines were measured in vitro; the results revealed that these metabolites have no cytotoxicity against the selected tumour cells.

Investigation of the roots of Beilschmiedia erythrophloia has led to the isolation of seven new endiandric acid analogues, erythrophloins A-F (1-6) and beilcyclone A (7), together with 11 known compounds. The structures of 1-7 were determined using spectroscopic techniques. Two constituents, erythrophloin C (3) and suberosol B (8), exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv, showing MIC values of 50 and 28.9 microg/mL, respectively.

Phytochemical investigation of the root of Beilschmiedia erythrophloia led to the isolation and structural elucidation of two new endiandric acid analogs, endiandric acids I and J (1 and 2, resp.), a new benzopyran, dehydrooligandrol methyl ether (3), and a new benzenoid, farnesylol (4), together with six known compounds. Their structures were established on the basis of extensive 1D- and 2D-NMR analyses in combination with HR-MS experiments.

Two new species of Rhagophthalmus Motschulsky, R. beigansis Ho sp. nov. and R. giallolateralus Ho sp. nov. collected in a vulnerable environment in two small islets of Matzu Archipelago, Lienchiang County are described and illustrated. This brings the total number of species in this genus to 35, and the number known from small off shore islets and islands to 10. Their importance to the conservation of such small and fragile island habitats is discussed.

isolation and structure of a new pyran-2-one derivative, monascuspyrone (I) along with nine known compounds

A chemical study of the EtOAc-soluble ethanolic extract of Monascus kaoliang BCRC 31506 (Eurotiaceae) fermented rice led to the isolation of a new furan-3-one derivative along with 9 known compounds, monascin (2), ankaflavin (3), N-trans-feruloyltyramine (4), vanillic acid (5), 4-acetonyl-3,5-dimethoxy-p-quinol (6), (+)-s-eudesmol (7), trans-phytol (8), aesculetin dimethyl ether (9) and (-)-matairesinol (10). Structure 1 is proposed for monascuskaoliaone on the basis of spectroscopic evidence (NMR, UV, IR, and HRMS). None of the compounds exhibited significant scavenging activity toward DPPH radical in bioautography or spectroscopic assays.