4957-67-9Relevant articles and documents
Catalytic, enantioselective α-additions of isocyanides: Lewis base catalyzed Passerini-type reactions
Denmark, Scott E.,Fan, Yu
, p. 9667 - 9676 (2005)
The generality of catalytic, enantioselective α-additions of isocyanides to aldehydes has been demonstrated (Passerini-type reactions). The catalytic system of silicon tetrachloride and a chiral bisphosphoramide (R,R)-1b provided high yields and good to excellent enantioselectivities for the addition of tert-butyl isocyanide to a wide range of aldehydes (aromatic, heteroaromatic, olefinic, acetylenic, aliphatic). Aqueous workup afforded the α-hydroxy tert-butyl amides whereas a low-temperature methanol quench followed by basic workup afforded the α-hydroxy methyl esters. The reaction is also successful for other isocyanides, albeit with reduced enantioselectivity. Reaction conditions, particularly the rate of addition of the isocyanide was found to be crucial for good yields and high selectivities.
Direct alkylative Passerini reaction of aldehydes, isocyanides, and free aliphatic alcohols catalyzed by indium(III) triflate
Yanai, Hikaru,Oguchi, Tomoko,Taguchi, Takeo
supporting information; experimental part, p. 3927 - 3929 (2009/10/01)
(Chemical Equation Presented) In(OTf)3 was found to be a useful Lewis acid catalyst for direct alkylative Passerini reaction of aldehydes, isocyanides, and free aliphatic alcohols. In the present reaction, aromatic and α,β-unsaturated aldehydes
The synthesis and some pharmacological actions of the enantiomers of the K+-channel blocker cetiedil
Roxburgh, Craig J.,Ganellin, C. Robin,Shiner, Mark A. R.,Benton, David C. H.,Dunn, Philip M.,Ayalew, Yeshi,Jenkinson, Donald H.
, p. 851 - 857 (2007/10/03)
Cetiedil ((±)-2-cyclohexyl-2-(3-thienyl)ethanoic acid 2-(hexahydro-1H-azepin-1-yl) ethyl ester) possesses anti-sickling and analgesic, antispasmodic, local anaesthetic and vasodilator activities. A total synthesis and circular dichroism spectra of the enantiomers of cetiedil is described, together with a comparison of their effectiveness as blockers of the Ca2+-activated K+ permeability of rabbit erythrocytes; the contractile response of intestinal smooth muscle to acetylcholine; the Ca2+-dependent contraction of depolarized intestinal muscle; and the cell volume-sensitive K+ permeability (K(vol)) of liver cells. The enantiomers did not differ substantially in their ability to block the Ca2+-activated K+ permeability of rabbit red cells or in their effectiveness as blockers of the contractile response of depolarized smooth muscle to externally applied Ca2+. There was a clear difference in the muscarinic blocking activity of the enantiomers, as assessed by inhibition of the contractile response of intestinal smooth muscle to acetylcholine; (+)-cetiedil was 7.7 ± 0.2 (s.d.) times more active than the (-) form. The enantiomers also differed in their potency as blockers of the increase in membrane conductance which occurs when liver cells swell. The concentration of (+)-cetiedil needed to reduce the conductance increase by 50% was 2.04 ± 0.54 (s.d.) μM; (-)-cetiedil was 2.6 ± 0.8 (s.d.) times less active (IC50 of 5.2 ± 1.2 μM). Differences in the biological actions of the enantiomers of cetiedil indicate that a more extensive study could be rewarding in relation to the use of the enantiomers both in therapeutics and in the study of K+ channels.
