A new sildenafil analogue, cyclopentynafil (1) and a new tadalafil analogue, N-octylnortadalafil (2) were isolated from a dietary supplement illegally marketed for erectile dysfunction. The structures of the sildenafil and tadalafil analogues were elucidated by using HPLC-photodiode array (PDA), LC-MS, high-resolution MS, NMR and circular dichroism (CD). These compounds were determined to be 5-...

Three new naphthoquinones and their analogues, named avicequinone-A (1), -B (2), -C (3), and avicenol-A (4), -B (5), -C (6), respectively, were isolated from the stem bark of Avicennia alba (Avicenniaceae) collected in Singapore, and their structures were elucidated by means of spectral methods. Gillan and co-workers have proposed that the structures of the new phytoalexins isolated from Avicen...

Salvia reuterana Bioss. is an aromatic perennial plant traditionally used for its anxiolytic and sedative properties. In the present study, various fractions and essential oil of S. reuterana aerial parts were investigated to find its free radical scavenging principles. Hydroalcoholic fraction with IC50 value of 112.6 ±3.2 μg ml-1 in DPPH assay demonstrated the highest free radical scavenging a...

N. fasciculare is a poisonous mushroom widely distributed in northeast part of Japan (Japanese name: Nigakuritake). Phytochemical investigation of this mushroom revealed some biologically active compounds which include new lanostane-type triterpenoids, fasciculols A-F [1 – 3]. In addition, N. fasciculare, when grown in liquid culture, produced a complex mixture of sesquiterpene metabolites of a...