Miroestrol (1) has been isolated previously as an active principle from "Kwao Keur" (Pueraria mirifica), a rejuvenating folk medicine from Thailand. Reinvestigation using bioassay-guided purification has resulted in the isolation of a new potent phytoestrogen, deoxymiroestrol (2). The facile aerial oxidation of 2 into 1 suggests the possibility that 1 may be an artifact.

Three new cyclobutanoid amides with trans-trans-trans configurations, piperarborenine C, piperarborenine D and piperarborenine E, and a new furanoid lignan, (+)-arborone, together with twelve known compounds, were isolated from the stems of Piper arborescens. The structures of these new compounds were determined by means of spectral analyses. Piperarborenine C, (+)-diayangambin, piplartine, piperolactam B, piperolactam C, aristolactam BIII, goniothalactam, and methyl trans-3,4,5-trimethoxycinnamate possessed anti-platelet aggregation activity in vitro. Among them, piplartine showed the most potent anti-platelet aggregation activity induced by collagen and showed an IC50 value of 21.5 microM. Piperarborenines A - E, piperarborenine, aristololactam BIII and goniothalactam showed significant cytotoxic activity (IC50 values < 4 microg/mL) against P-388, HT-29 and A549 cell lines in vitro.

We measured longitudinal and transverse relaxation times (T(1) and T(2)) for (1)H, (13)C-T(1) and (13)C spectra for room-temperature ionic liquids of 1-alkyl-3-methylimidazolium bromide [C(n)mim]Br (n = 2, 3, 4) as a function of temperature. Their values and spectra reveal close relationships between their unique phase behaviours and the dynamics of carbons constituting the cations. Carbons in these cations are classified into groups according to their dynamics, namely imidazolium carbons, an N-methyl carbon, a terminal methyl carbon of the alkyl group and others of the alkyl group. The temperature dependences of T(1) values for these groups differ greatly, resulting in a variation in the characteristic thermal behaviours of the salts. Values of (1)H-T(1) and (13)C-T(1) suggest that some carbons continue to move even in the crystalline and/or solid states. Using (13)C-T(1) data, we also estimated the temperature dependences of the correlation times for the segmental motions of carbons in the liquid states.