L-prolinamides

CN 6-[O-(l,l-dimethylethyl)-D-serine]-9-(N-ethyl L-prolinamide)-10-deglycinamideIuteinizing hormone-releasing factor (pig)... 

L-proline and L-prolinamide, respectively. In both cases, the remaining (/ ru,5)-8 is free to catalyze the asymmetric Diels-Alder reaction. 

Leuprolide Leuprolide, 5-oxo-L-prolyl-L-histadyl-L-tryptophyl-L-seryl-L-tyrosyl-D-leu-cil-L-leucil-L-arginyl-iV-ethyl-L-prolinamide (30.5.9), is made synthetically [136-139]. 

A-(4-Methoxysuccinyl)-L-valyl-/V-(I-benzyl-3,3,3-trifluoro-2-hydroxypropyl)-L-prolinamide (23, R =Bzl R2=MeOSu-Val-Pro) [201... 

In direct nitroso aldol reactions of a-branched aldehydes, an L-prolinamide (50) catalyses to give a-hydroxyamino carbonyl compounds which are otherwise dis- favoured ees up to 64% were found.149 Another prolinamide derivative gives similar results in a nitrosobenzene reaction.150 For proline-catalysed cases involving highly substituted cyclohexanones, DFT calculations have highlighted the roles of electro- static and dipole-dipole interactions in the level of de achieved.151 (g)... 

L-Prolinamides (71) with a pendant alcohol act as recoverable bifunctional catalysts of direct nitro-Michael addition of ketones to -nitrostyrenes, giving syn-de s up to 94% and ees up to 80%.204 The pyrrolidine provides enamine catalysis, and the side-chain donors can hydrogen-bond the nitro oxygens. 

NBD-amino acids (serine, threonine, valanie, phenylalanine, and histidine) were separated by using a 20 mM ammonium acetate buffer (pH 9.0) containing 10 mM copper acetate, 20 mM L-prolinamide, and 1 mM SDS. The elution order was the L-enantiomer followed by the D-form except in NBD-histidine. Weng et al. [32] described chiral separation of tryptophan on a poly(methyl methacrylate) microfluidic chip coated with bovine serum albumin (32 mm... 

Chemical Name L-Prolinamide, N-((4-oxo-2-azetidinyl)carbonyl)-L-histidyl-,... 

In 13 ml of DMF was dissolved 826.0 mg of L-histidyl-L-prolinamide 2-hydrobromide and then 2 ml of a DMF solution of 405.0 mg of triethylamine was added to the solution under ice-cooling. After maintaining 30 min under ice-cooling, the precipitates thus formed were filtered off to provide L-histidyl-L-prolinamide. 

CN (i- 0-( 1,1 -dimethylethyl)-D-serine]-9-( V-ethyl-l.-prolinamide)-10-(jcglycinamidclulcinizing hormone-... 

The leaves of Arnica montana L. contain a new alkaloid, N-ethoxycarbonyl-L-prolinamide (1). Its structure has been established by mass, i.r., and n.m.r. spectral analysis, and confirmed by synthesis from L-proline by conversion into the amide followed by reaction with ethyl chloroformate. The synthesis also settles the absolute configuration of the new alkaloid.3... 

Most small peptides derived from protein sources contain a variety of polar and non-polar amino acids and as such are more difficult to handle. Nevertheless appreciation of the problems and considered chemical manipulation have allowed their MS elucidation [177-184] although a practical limit of about six amino acids in the peptide is reached before degradative procedures become advisable. An important step before sequencing a peptide by mass spectrometry is whenever possible to obtain the amino acid content by hydrolysis and conventional column chromatographic analysis. This assists in the selection of any chemical pretreatment and with the spectral interpretation. A variety of small peptides has been identified by a combination of methods and include 5 - 0X0 - L - prolyl - L - histadyl - L - prolinamide (2-pyrollidone-5-carboxylyl-... 

TLC using silica gel coated with an L-prolinamide-copper(II) salt mixture (Chiralplates Macherey-Nagel Co.) separates enantiomers using the ligand-exchange principle to give information on the chiral purity of amino acids and peptides. The equivalent HPLC procedure has been used for determining enantiomer ratios. 

Ovuplant (Fig. 4) is a cylindrical subcutaneous implant containing the synthetic GnRH analog Deslorelin [6-D-tryptophan-9-(Ar-ethyl-L-prolinamide)-10-desglycinamide]. The implant is 2.3 mm in diameter and 3.6 mm in length and contains 2.1 mg of Deslorelin... 

By using of a modified proline, L-prolinamide 47 (which is known to be a more reactive catalyst than L-proline in cross-aldol reactions [80]), the enantioselectivity of the direct aldol reactions in ionic liquid [bmim][BF4] was remarkably increased as compared with the reaction carried out in acetone (69% ee) (Scheme 7.26) [81]. However, the reusability of the recovered 47 when immobilized in the ionic liquid layer was somewhat inferior to that of the L-proline catalyst this effect could be ascribed to the increased solubility of the organocatalyst 47 in the extracting organic solvents (not provided in the literature), leading to an increased leaching of the catalyst. 

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