PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 22684237-1 2012 A diastereo- and enantioselective aldol reaction between aldehydes and a synthetically useful ketomalonate 1c as a hydrated form was developed, and either anti- or syn-aldol adducts having a chiral tetrasubstituted carbon center were obtained in high enantioselectivities by use of a tetrazole analogue of L-proline (S)-2 or an axially chiral amino sulfonamide (S)-3 as catalyst. Proline 306-315 synemin Homo sapiens 73-76 23101761-1 2012 The choice of the anion of an achiral TBD-derived guanidinium salt, used as cocatalyst for proline, allows reacting cycloketones with aromatic aldehydes and preparing either anti- or syn-aldol adducts with very high enantioselectivity. Proline 91-98 synemin Homo sapiens 183-186 23101761-3 2012 The origin of the syn diastereoselectivity unfolds from an unusual equilibrium process coupled to the enamine-based catalytic cycle standard for proline. Proline 145-152 synemin Homo sapiens 18-21 22500641-3 2012 Modified prolines with aromatic groups syn to the carboxylic acid are better catalysts than those with small hydrophobic groups (1a is 43.5 times faster than 1f). Proline 9-17 synemin Homo sapiens 39-42 22486203-3 2012 We report here both syn- and anti-selective asymmetric direct Mannich reactions of N-protected aminoacetaldehydes with N-Boc-protected imines catalyzed by proline and the axially chiral amino sulfonamide (S)-3. Proline 155-162 synemin Homo sapiens 20-23 19938836-1 2009 Dipeptides obtained from l-proline and beta(3)-l-amino acids are reported to catalyze enantioselective direct aldol reaction in aqueous medium, leading to significant anti:syn diastereomeric ratios and enantiomeric excesses. Proline 25-34 synemin Homo sapiens 172-175 21999103-1 2011 A chemo- and stereoselective asymmetric direct cross-aldol reaction between aliphatic aldehydes and alpha-chloroaldehydes has been developed as a method for the formation of the sole cross-aldol adduct with both enantio- and diastereocontrol, and either anti- or syn-aldol adducts were obtained in good to excellent stereoselectivities by use of proline or a novel axially chiral amino sulfonamide as catalyst. Proline 346-353 synemin Homo sapiens 263-266 21958056-1 2011 Proline anthranilamide-based pseudopeptides were shown to be effective organocatalysts for enantioselective direct aldol reactions of a selection of aldehydes with various ketones with excellent yield, enantioselectivity up to 99% and anti to syn diastereoselectivity up to 25:1. Proline 0-7 synemin Homo sapiens 243-246 21932236-2 2011 Excellent yields (up to 93%) and a significant improvement in diastereoselectivity (anti/syn up to 45:1) as well as enantioselectivity (up to more than 99% ee) compared with using proline as the sole catalyst were observed. Proline 180-187 synemin Homo sapiens 89-92 20476722-0 2010 Enantioselective synthesis of syn/anti-1,3-amino alcohols via proline-catalyzed sequential alpha-aminoxylation/alpha-amination and Horner-Wadsworth-Emmons olefination of aldehydes. Proline 62-69 synemin Homo sapiens 17-20 19449895-0 2009 Iterative approach to enantiopure syn/anti-1,3-polyols via proline-catalyzed sequential alpha-aminoxylation and Horner-Wadsworth-Emmons olefination of aldehydes. Proline 59-66 synemin Homo sapiens 34-37 18549281-3 2008 B3LYP/6-31+G** calculations provide a good explanation for the opposite syn vs anti diastereoselectivity of these two kinds of amino acid catalysts (anti-selectivity for the secondary cyclic amino acids proline, syn-selectivity for the acyclic primary amino acids like threonine). Proline 203-210 synemin Homo sapiens 72-75 19405512-2 2009 The key steps include diastereoselective proline-catalyzed syn aldol transformation and a reductive amination/cyclization. Proline 41-48 synemin Homo sapiens 59-62 16494447-3 2006 In contrast, (S)-proline-catalyzed reactions give mainly syn-products with high enantioselectivities. Proline 13-24 synemin Homo sapiens 57-60 16866507-5 2006 (S)-Proline or (S)-2-pyrrolidinecarboxylic acid has been reported to catalyze the Mannich-type reactions of ketones to afford the syn-products. Proline 0-11 synemin Homo sapiens 130-133 16866507-5 2006 (S)-Proline or (S)-2-pyrrolidinecarboxylic acid has been reported to catalyze the Mannich-type reactions of ketones to afford the syn-products. Proline 15-47 synemin Homo sapiens 130-133 16494447-4 2006 Computational studies reveal that the energetic preference between the transition structures involving the s-cis-enamine and the s-trans-enamine is smaller for the pipecolic acid as compared to proline, yielding the (2S,3R)-anti and the (2S,3S)-syn Mannich product in nearly equal amounts. Proline 194-201 synemin Homo sapiens 245-248 7118423-2 1982 spectroscopy, we have investigated cis-trans isomerism for N-acetyl, N"-methylamide derivatives of syn- and anti-5-methylproline (syn: the methyl group and carboxamide are on the same side of the proline ring, anti: on opposite sides). Proline 121-128 synemin Homo sapiens 130-133 16433496-2 2006 Based on principles gained from the study of (S)-proline-catalyzed Mannich-type reactions that afford enantiomerically enriched syn-products, (3R,5R)-5-methyl-3-pyrrolidinecarboxylic acid (RR35) has been designed to catalyze the direct enantioselective anti-selective Mannich-type reactions. Proline 45-56 synemin Homo sapiens 128-131 14656102-1 2003 N-Tritylprolinal (prepared in four steps from l-proline) shows a very high Felkin diastereoselectivity in its reaction with various nucleophiles, leading to a straightforward and highly stereoselective access to syn-proline-derived amino alcohols. Proline 46-55 synemin Homo sapiens 212-215 7118423-3 1982 For Ac-syn-5-MeProNHMe, we observe about 25% cis peptide bond isomers in most solvents as is common for oligopeptides of proline. Proline 121-128 synemin Homo sapiens 7-10 32459490-3 2020 A syn-selective self-Mannich reaction catalyzed by proline is utilized for the asymmetric synthesis of the diastereomer, (+)-laburnine, and its enantiomer, (-)-trachelanthamidine. Proline 51-58 synemin Homo sapiens 2-5 28513914-3 2017 Proline and acid groups appended to catalytic fibers of two self-sorting hydrogelators compete for the Mannich reaction between aniline, benzaldehyde, and cyclohexanone to give low overall selectivity (anti/syn 77:23). Proline 0-7 synemin Homo sapiens 207-210 28513914-4 2017 In a sol-gel system of the same molecules, on the other hand, the soluble acid appended molecules tend to cooperate with the fibers of proline-appended catalyst to give improved selectivity (anti/syn 95:5). Proline 135-142 synemin Homo sapiens 196-199 25594676-0 2015 Proline-catalyzed sequential syn-Mannich and [4 + 1]-annulation cascade reactions to form densely functionalized pyrrolidines. Proline 0-7 synemin Homo sapiens 29-32 26991332-2 2016 The combination of proline and a urea Bronsted base cocatalyst is key for the reactions to proceed under very mild conditions (3-10 mol % catalyst loading, dichloromethane as solvent, -20 C, 1.2 molar equivalents of aldehyde) and with virtually total stereocontrol (syn/anti ratio up to 99:1; ee up to 99 %). Proline 19-26 synemin Homo sapiens 267-270 25594676-2 2015 The in situ generated syn-Mannich adduct obtained via proline catalysis acts as a four-atom component, and Corey"s sulfur ylide or ethyl bromoacetate acts as a one-atom carbon source to construct pyrrolidine units in a highly enantio- and diastereoselective manner. Proline 54-61 synemin Homo sapiens 22-25 23442005-4 2013 DFT calculations not only provide a good explanation for the formation of the sole cross-aldol product between two aliphatic aldehydes both bearing alpha-methylene protons but also well reproduce the opposite syn vs anti diastereoselectivities in the chiral amino sulfonamide and proline-catalyzed aldol reactions. Proline 280-287 synemin Homo sapiens 209-212