- Inhibition of imidazolidinone intermediate formation in the aldol reactions catalyzed by zinc-prolinamide complexes
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The use of zinc salts as cocatalysts in aldol condensations catalyzed by single prolinamide (and in the extension by other more complex prolinamides) can prevent the formation of the parasitic intermediate imidazolidinone, with faster and also more stereoselective reactions than those catalyzed by the free amine. This new finding, together with this ion's already known properties, make zinc salts highly suitable additives for aldol reactions catalyzed for prolinamide derivatives.
- Andreu, Cecilia,Varea, Teresa,Asensio, Gregorio
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- Influence of silaproline on peptide conformation and bioactivity
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The analogue γ-(dimethylsila)-proline, denoted silaproline (Sip), was synthesized in both enantiomerically pure forms by diastereoselective alkylation of a chiral glycine equivalent with use of Schoellkopf's bis-lactim ether method. The effect of replacing a proline residue in model peptides by this new proline surrogate has been examined in the crystal state by X-ray diffraction and in solution by IR absorption and NMR techniques. Silaproline and proline-containing sequences exhibit very similar conformational properties. Silaproline was also substituted for proline in a neurotensin (8-13) analogue that retained biological activity and exhibited enhanced resistance to biodegradation.
- Cavelier, Florine,Vivet, Bertrand,Martinez, Jean,Aubry, Andre,Didierjean, Claude,Vicherat, Andre,Marraud, Michel
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- QUINAZOLINEDIONE DERIVATIVE
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The present invention relates to quinazolinedione derivatives represented by formula (I) or pharmaceutically acceptable salts thereof.
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Paragraph 1651; 1653
(2015/03/16)
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- Structure-activity relationship of orally potent tripeptide-based HIV protease inhibitors containing hydroxymethylcarbonyl isostere
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We designed and synthesized a new class of peptidomimetic human immunodeficiency virus protease inhibitors containing a unique unnatural amino acid, allophenylnorstatine [Apns; (2S,3S)-3-amino-2-hydroxy-4-phenylbutyric acid], with a hydroxymethylcarbonyl isostere as the active moiety. From a structure-activity relationship study of HIV-1 protease inhibition, enzyme selectivity for other aspartyl proteases, the antiviral activity and pharmacokinetics in rats, 24c (KNI-227) and 24d (KNI-272, our first clinical candidate) were found to be selective and orally potent HIV protease inhibitors. Moreover, an improvement of the pharmacokinetic features of KNI-272 provided two long-lasting and highly bioavailable compounds (24g: JE-2178,h: JE-2179).
- Mimoto, Tsutomu,Hattori, Naoko,Takaku, Haruo,Kisanuki, Sumitsugu,Fukazawa, Tominaga,Terashima, Keisuke,Kato, Ryohei,Nojima, Satoshi,Misawa, Satoru,Ueno, Takamasa,Imai, Junya,Enomoto, Hiroshi,Tanaka, Shigeki,Sakikawa, Hiroshi,Shintani, Makoto,Hayashi, Hideya,Kiso, Yoshiaki
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p. 1310 - 1326
(2007/10/03)
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