2791-29-9Relevant articles and documents
A simple and practical synthetic protocol for acetalisation, thioacetalisation and transthioacetalisation of carbonyl compounds under solvent-free conditions
Khan, Abu T.,Mondal, Ejabul,Ghosh, Subrata,Islam, Samimul
, p. 2002 - 2009 (2007/10/03)
A wide variety of carbonyl compounds can be converted smoothly to the corresponding acetals on treatment with alcohols or diols and triethyl orthoformate in the presence of a catalytic amount of (bromodimethyl)sulfonium bromide at room temperature. Similarly, various carbonyl compounds can be transformed into the corresponding dithioacetals on reaction with thiol or dithiols at room temperature by employing the same catalyst without any solvent. Moreover, O,O-acetals can also be converted into the corresponding dithioacetals under identical conditions. Some of the major advantages are mild reaction conditions, a high degree of efficiency, compatibilty with other protecting groups and the lack of solvents, particularly for thioacetalisation. In addition, no brominations occur at the double bond or α to the keto position or even in the aromatic ring under these experimental conditions. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
Darmstoff Analogues. 3. Actions of Choline Esters of Acetal Phosphatidic Acids on Visceral Smooth Muscle
Marx, Michael H.,Wiley, Robert A.,Satchell, D. G.,Maguire, M. Helen
, p. 1319 - 1322 (2007/10/02)
A number of naturally occurring phospholipids, e.g. the acetal phosphatidic acid derivatives that comprise Darmstoff (1) and the phosphatidylcholine derivative platelet activating factor (PAF), cause contraction of certain visceral smooth muscles and cause platelet activation.Because the Darmstoff phosphatidic acids and PAF are structurally similar, it was of interest to compare the biological actions of choline esters of Darmstoff with those of PAF and of the parent Darmstoff phosphatidic acids.To this end, phosphocholine (3a), methyl>phosphocholine (3b), and methyl>phosphocholine (3c) were synthesized.Compounds 3a, 3b, 3c, and PAF caused dose-dependent relaxation of taenia coli strips.In contrast, the unesterified materials 1a and 1b, as well as lyso-PAF, caused contraction in taenia coli strips.Thus, the contractile effect of Darmstoff is reversed on esterification with choline.In preparations of whole trachea, both 1a and 3a had contractile effects similar to those of PAF.
