Chemical compounds isolated from Talinum triangulare (Portulacaceae)

This first phytochemical study of Talinum triangulare Leach (Portulacaceae), also known as 'cariru', which is a commonly consumed food in Northern Brazil, allowed the isolation and structural determination of four new compounds: one acrylamide, 3-N-(acryloyl, N-pentadecanoyl) propanoic acid (5), and three new phaeophytins named (151S, 17R, 18R)-Ficuschlorin D acid (31,32-didehydro-7-oxo-173-O-phytyl-rhodochlorin-15-acetic acid), (13), Talichorin A (17R, 18R)-phaeophytin b-151-hidroxy, 152,153-acetyl-131-carboxilic acid (14), and (151S, 17R, 18R)-phaeophytin b peroxylactone or (151S, 17R, 18R)-hydroperoxy-ficuschlorin D (16), together with twelve known compounds, including four phaeophytins (11,12, 15 and 17). The structures of the compounds were established on the basis of 1D and 2D NMR, IR, HRESI-MS spectra, including GC-MS, and HPLC-UV analysis, as well as comparisons with the literature data. The CD spectra data analysis were used to define the absolute configuration of phaeophytins 12 (132R, 17R, 18R)-132-hydroxyphaeophytin a, 13 and 16, 15 (151S, 17R, 18R)-31,32-didehydro-151-hydroxyrhodochlorin-15-acetic acid δ-lactone-152-methyl-173-phytyl ester and 17 (17R, 18R)-purpurin 18-phytyl ester.