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The photoreaction of 2,3,4',5-tetrahydroxystilbene-2- O -β-d-glucoside (TSG) has been investigated. Water-assisted/water-accelerated photodimerization of trans -TSG favored the formation of syn -head-to-tail [2 + 2] photocyclobutane under 365 nm irradiation as a result of hydrophobic association and a fluorescent solute-solute aggregate from their excited singlet states. In contrast, irradiation with 254 nm led to [2 + 2] photocycloreversion. The two cyclobutane dimers were first obtained through straightforward photoreaction and identified as multiflorumiside A and multiflorumiside C through the detailed analysis of high-resolution electrospray ionization mass spectrometry and one- and two-dimensional nuclear magnetic resonance. Therefore, trans -TSG should be protected from light and water.

Six new 9,19-cycloartane triterpene derivatives, as well as 3 known analogues (7-9), were isolated from the roots of Cimicifuga foetida L. Their structures were established on the basis of extensive spectroscopic analyses (IR, UV, ORD, HRESIMS, 1D and 2D NMR).

Four new 9,19-cycloartane triterpenoids, cimilactone E ( 1 ), cimilactone F ( 2 ), 2'- O -( E )-butenoyl-23- epi -26-deoxyactein ( 3 ), and 2',12 β - O -diacetylcimiracemonol-3- O - β -d-xylopyranoside ( 4 ), together with four known constituents ( 5 - 8 ) were isolated from the roots of Cimicifuga foetida . The new structures were elucidated by extensive spectroscopic analysis. In addition, compounds 7 and 8 showed significant Wnt signaling pathway inhibitory activity, with IC 50 values of 3.33 and 13.34 μM, respectively, using the luciferase reporter gene assay.

Six new 9,19-cycloartane triterpenes (1-6) were isolated from the aerial parts of Cimicifuga yunnanensis. The new chemical structures were determined by extensive analyses of 1D and 2D NMR spectroscopy. Compounds 1 and 2 are the first 9,19-cycloartane triterpenes characterized by CH₃-18 shifting from C-13 to C-12 in the Cimicifuga spp. The evaluation of inhibition activity against human HL-60, SMMC-7721, A-549, MCF-7, and SW480 cell lines indicated that compounds 1-6 showed different levels of cytotoxic activities with IC₅₀ values ranging from 1.2 to 27.8 μm., (Copyright © 2014 Elsevier B.V. All rights reserved.)