705250-77-7Relevant articles and documents
Mizoroki-Heck Reaction of Unstrained Aryl Ketones via Ligand-Promoted C-C Bond Olefination
Wang, Mei-Ling,Xu, Hui,Li, Han-Yuan,Ma, Biao,Wang, Zhen-Yu,Wang, Xing,Dai, Hui-Xiong
, p. 2147 - 2152 (2021/04/05)
Mizoroki-Heck reaction of unstrained aryl ketone with acrylate/styrene is accomplished via palladium-catalyzed ligand-promoted C-C bond cleavage. Various (hetero)aryl ketones are compatible in the reaction, affording the alkene product in good to excellent yields. Further applications in the late-stage olefination of some drugs, natural products, and fragrance-derived aryl ketones demonstrate the synthetic utility of this protocol. By employing ketone as both the directing group and the leaving group, 1,2-bifunctionalization is achieved via sequential ortho-C-H alkylation/ipso-Heck olefination.
Exploring distal regions of the A3 adenosine receptor binding site: Sterically constrained N6-(2-phenylethyl)adenosine derivatives as potent ligands
Tchilibon, Susanna,Kim, Soo-Kyung,Gao, Zhan-Guo,Harris, Brian A.,Blaustein, Joshua B.,Gross, Ariel S.,Duong, Heng T.,Melman, Neli,Jacobson, Kenneth A.
, p. 2021 - 2034 (2007/10/03)
We synthesized phenyl ring-substituted analogues of N6-(1S,2R)- (2-phenyl-1-cyclopropyl)adenosine, which is highly potent in binding to the human A3AR with a Ki value of 0.63nM. The effects of these structural changes on affinity at human and rat adenosine receptors and on intrinsic efficacy at the hA3AR were measured. A 3-nitrophenyl analogue was resolved chromatographically into pure diastereomers, which displayed 10-fold stereoselectivity in A3AR binding in favor of the 1S,2R isomer. A molecular model defined a hydrophobic region (Phe168) in the putative A3AR binding site around the phenyl moiety. A heteroaromatic group (3-thienyl) could substitute for the phenyl moiety with retention of high affinity of A3AR binding. Other related N6-substituted adenosine derivatives were included for comparison. Although the N 6-(2-phenyl-1-cyclopropyl) derivatives were full A3AR agonists, several other derivatives had greatly reduced efficacy. N 6-Cyclopropyladenosine was an A3AR antagonist, and adding either one or two phenyl rings at the 2-position of the cyclopropyl moiety restored efficacy. N6-(2,2-Diphenylethyl)adenosine was an A 3AR antagonist, and either adding a bond between the two phenyl rings (N6-9-fluorenylmethyl) or shortening the ethyl moiety (N 6-diphenylmethyl) restored efficacy. A QSAR study of the N 6 region provided a model that was complementary to the putative A3AR binding site in a rhodopsin-based homology model. Thus, a new series of high-affinity A3AR agonists and related nucleoside antagonists was explored through both empirical and theoretical approaches.