6443-75-0Relevant articles and documents
Bibenzyl- and stilbene-core compounds with non-polar linker atom substituents as selective ligands for estrogen receptor beta
Waibel, Michael,De Angelis, Meri,Stossi, Fabio,Kieser, Karen J.,Carlson, Kathryn E.,Katzenellenbogen, Benita S.,Katzenellenbogen, John A.
experimental part, p. 3412 - 3424 (2009/10/23)
A series of structurally simple bibenzyl-diol and stilbene-diol core molecules, structural analogs of the well-known hexestrol and diethylstilbestrol non-steroidal estrogens, were prepared and evaluated as estrogen receptor (ER) subtype-selective ligands. Analysis of their ERα and ERβ binding showed that certain substitution patterns engendered binding affinities that were >100-fold selective for ERβ. When further investigated in cell-based gene transcription assays, some molecules showed similarly high relative transcriptional potency selectivity in favor of ERβ. Interestingly, the most ERβ-selective molecules were those bearing non-polar substituents on one of the internal carbon atoms. These compounds should be useful probes for determining the physiological roles of ERβ, and they might lead to the development of more selective and thus safer pharmaceuticals.
Photochemistry of α-Aryl Carboxylic Anhydrides. Part 4. Photoreactions of Some Asymmetrical Anhydrides derived from o- and p-Methoxyphenylacetic Acid, and of Some of the Phenylacetate Ester Photoproducts
Roof, Antonius A. M.,Woerden, Hendrik F. van,Cerfontain, Hans
, p. 838 - 841 (2007/10/02)
Irradiation of the two asymmetrical carboxylic anhydrides R1C6H4CH2.CO.O.CO.CH2C6H5 (1a and 1b) at 254 nm in acetonitrile leads to the formation of esters and bibenzyls.Among the esters produced, the asymmetrical ones with structure R1C6H4CH2.O(C=O)CH2C6H5 are the most abundant.These are for the greater part formed intramolecularly by decarbonylation of one excited anhydride molecule.This result is in line with a mechanism involving electron transfer after excitation of the anhydride molecule.The bibenzyls are formed by the recombination of benzyl radicals.In the initial stage of the reaction of the anhydrides, the three bibenzyls are formed with the asymmetrical one predominating .In the later stages, when substantial amounts of esters are present, the formation of the bibenzyls also originates in part from the photodecomposition of the esters.The photochemistry of the various (symmetrical and asymmetrical) esters which are photoproducts from the anhydrides (1a and b) has also been studied.The symmetrical esters (2a and b) afforded quantitatively the bibenzyls (3a and b), respectively.The asymmetrical esters gave variable yields of the three (possible) bibenzyls, depending on the type of ester considered.For the asymmetrical esters for which bibenzyl formation could be quenched by (Z)-piperylene, the three bibenzyls were formed in a close to statistical ratio, e.g. (2c) yielded the bibenzyls (3a, c, and e) in a ratio of 1:2.5:1.With the esters for which the photodecarboxylation was not quenchable by (Z)-piperylene, a relatively higher yield of the asymmetrical bibenzyl was found, e.g. (2d) yielded the bibenzyls (3b, d, and e) in a ratio of 1:6:1.These results are rationalized in terms of a recombination of free radicals resulting from the triplet excited esters after spin inversion in the former case, and a recombination of a radical pair in the solvent cage resulting from the singlet excited or shortlived triplet excited ester in the latter case.
