An efficient and feasible synthetic approach was developed for the synthesis of an array of new flavane derivatives from the substituted benzaldehyde with the reduction of chalcones and subsequent cyclization as the key steps. The purity and structure of the products were confirmed by the elemental analysis and a combination of its IR, ¹H and ¹³C NMR, and mass spectra. These synthetic compounds were tested for xanthine oxidase (XO) inhibitions and antifungal actions against Candida albicans, Cryptococcus neoformans, Aspergillus sp. and Trichophyton rubrum. 7-Hydrazinocarbonylmethoxy-4′-methoxyflavane (9) was found to be the most XO inhibitory with IC₅₀=76.4 µmol/L, and the most potent antifungal compound was 4′-hydrazinocarbonylmethoxyflavane (12) with minimal inhibition concentration MIC8 μg/mL against Trichophyton rubrum.

Lophenol, cholest-4α-methyl-7-en-3β-ol (1), obtained from Dracaena cochinchinensis (Lour.) S. C. Chen, was structurally modified. It was acetylated to protect 3β-hydroxyl group, and then oxidised by selenium dioxide in ace-tic acid to give cholest-4α-methyl-8-en-3β,7α-diol diacetate (3). This compound 3 is unstable in chloroform solution or when heated and easily converted to a diene compound, cholest-4α-methyl-7,14-dien-3β-ol acetate (4). The structures of 3 and 4 were elucidated by means of IR, ¹H NMR, ¹³C NMR and MS, and the absolute configuration of 3 was established by X-ray crystallography. The property of 3 was also discussed in this paper. Both 3 and 4 are new compounds and were reported for the first time.

A new compound, Cochinchin (1), together with 7,4′-dihydroxyflavone (2), 7-hydroxy-4′-methoxyflavane (3). 7-hydroxy-3-(4-hydroxybenzyl)chroman (4), 4′-hydroxy-2,4-dimethoxydihydrochalcone (5) and 4′-hydroxy-2,4,6-trimethoxydihydrochalcone (6) was isolated from the resin (trivial name, “dragon's blood”) of Dracaena cochinchinensis (Lour.) S. C. Chen. The structure of 1 was elucidated on the basis of spectroscopic data as (2,3-trans)-6-allyl-2-(3,5-dimethoxyphenyl)-3-(4-hydroxyphenyl)-2,3-dihydrobenzo[1,4]dioxin which is a natural product possessing a new framework.