136160-47-9Relevant academic research and scientific papers
Synthesis of the atropurpuran A-ring via an organocatalytic asymmetric intramolecular Michael addition
Chen, Huan,Zhang, Dan,Xue, Fei,Qin, Yong
, p. 3141 - 3148 (2013/05/09)
The asymmetric synthesis of the A-ring fragment 2a-b of atropurpuran 1 has been achieved in 15 steps with up to 70% ee via an organocatalytic intramolecular Michael addition of nitroalkene 10. The absolute configuration of the two contiguous carbon center
Construction of carbo- And heterocycles using radical relay cyclizations initiated by alkoxy radicals
Zhu, Hai,Wickenden, Jason G.,Campbell, Natalie E.,Leung, Joe C. T.,Johnson, Kayli M.,Sammis, Glenn M.
supporting information; experimental part, p. 2019 - 2022 (2009/09/08)
An efficient method for the rapid construction of carbo- and heterocycles has been developed using radical relay cyclizations initiated by alkoxy radicals. Linear substrates were cyclized to form a wide range of cyclopentane, pyrrolidine, tetrahydropyran, and tetrahydrofuran derivatives in excellent yields. This methodology was utilized as a key step in the synthesis of the tetrahydrofuran fragment in (-)-amphidino-lide K.
Agents combining thromboxane receptor antagonism with thromboxane synthase inhibition: [[[2-(1H-imidazol-1-yl)ethylidene]amino]oxy]alkanoic acids
Cozzi,Giordani,Menichincheri,Pillan,Pinciroli,Rossi,Tonani,Volpi,Tamburin,Ferrario,Fusar,Salvati
, p. 3588 - 3604 (2007/10/02)
A new class of compounds combining thromboxane-A2 (TxA2) receptor antagonism and thromboxane synthase inhibition is described. A first series of (E)- and (Z)-[[[2-(1H-imidazol-1-yl)ethylidene]amino]oxy]pentanoic acids showed relevant thromboxane synthase inhibition associated with weak TxA2 receptor antagonism, while a series of (±)-(E)-[[[2-(1H-imidazol-1-yl)-3- phenylpropylidene]amino]oxy]pentanoic acids, structurally derived from the former, showed potent and well-balanced dual activity. Structural requirements for significant single and dual activity are discussed. Two close congeners of the latter series, (±)-(E)-5-[[[1-cyclohexyl-2-(1H- imidazol-1-yl)-3-phenylpropylidene]amino]oxy]pentanoic acid 23c and its p- fluorophenyl analog 23m, inhibited TxB2 production in vitro, in rat whole blood during clotting, with IC50 of 0.06 and 0.37 μM and antagonized the binding of [3H]SQ 29548 to washed human platelets, with IC50 of 0.08 and 0.02 μM, respectively. These two compounds were selected for further pharmacological evaluation and were shown to antagonize U46619-induced platelet aggregation in human platelet rich plasma with IC50 of 0.30 and 0.44 μM, respectively. They were both orally available, and in particular 23m caused a long lasting ex vivo TxA2 synthase inhibition in the fed rat. The levorotatory enantiomer of 23c, stereospecifically synthesized as a model compound, was found to be more potent than racemic 23c with regard to TxA2 receptor antagonism (IC50 = 0.04 μM) and equivalent to the latter with regard to TxA2 synthase inhibition. A molecular modeling study concerning the levorotatory enantiomer of 23c (S), TxA2, and representative TxA2 antagonists of different classes led to the definition of a putative pharmacophoric model for the TxA2 receptor ligands.
Intramolecular anodic olefin coupling reactions and the use of vinylsilanes
Hudson, Christine M.,Moeller, Kevin D.
, p. 3347 - 3356 (2007/10/02)
Intramolecular anodic olefin coupling reactions involving vinylsilane groups have been studied. It was found that the previously successful predictive model for olefin coupling reactions based on an electrophilic attack of a radical cation onto an olefin did not successfully predict product formation for olefin coupling reactions involving vinylsilane terminating groups. Instead, these reactions were best described by viewing the initial addition of the radical cation to an olefin as if it occurred in a reversible "radical-like" fashion. In addition, reactions using a temporary silicon tether were shown to be compatible with the formation of quaternary carbons with control of relative stereochemistry. These reactions helped highlight the compatibility of the anodic olefin coupling reactions with extremely sensitive substrates. Finally, the results reported suggest that the mass balance of the intramolecular anodic olefin coupling reaction depends on the ease with which the initially formed cyclized product undergoes the second oxidation step.
