Un nouvel acide amine dans les graines de Vigna vexillata

A new natural amino acid, l-(+)-p-aminophenylalanine, has been isolated from a legume, Vigna vexillata (L.) A. Rich. Its structure was determined and confirmed by synthesis.     

l-2-Oxalylamino-3-aminopropionic acid,an isomer of Lathyrus sativus neurotoxin

The first chemical synthesis of l-2-oxalylamino-3-aminopropionic acid, an isomer of the Lathyrus sativus neurotoxin, is described. Studies on its biological properties are reported. Experiments with l-3-[¹⁴C-oxalyl]amino-2- aminopropionic acid show that the amount of 2-oxalylamino isomer detectable in seed extracts can be accounted for by rearrangement which occurs during isolation.     

Tyrosine O-glucoside and dopamine 3-O-glucoside in seeds of Entada pursaetha

l-Tyrosine O-glucoside (I) and dopamine-3-O-glucoside (II) have been isolated from seeds of Entada pursaetha DC. The structures have been established by spectroscopic methods, identification of hydrolysis products and comparison with synthetic material. Syntheses are described of II, dopamine 4-glucoside and tyramine-O-glucoside.     

Methyl-4 formyl-7 cyclopenta(c)pyranne isole apres hydrolyse acide de Viburnum tinus

Viburtinal (4-methyl-7-formylcyclopenta(c)pyrane), yet unknown, was obtained by acid hydrolysis of the esters extracted from Viburnum tinus. Its structure was deduced by spectroscopic methods.     

Dimorphism of β-n-oxalyl-l-α, β-diaminopropionic acid

The neurotoxic non-protein amino acid, β-N-oxalyl-l-α, β-diaminopropionic acid (β-ODAP) exists in two crystalline modifications; a metastable monohydrate and a thermodynamically stable anhydrous form. Reproducible methods for preparing each polymorph are described and their structures are discussed on the basis of their general physical characteristics and their IR spectra and X-ray powder patterns. The ionic properties of the amino acid were studied in solution and revised pKina values for the two carboxyl functions are reported.     

2(S)-Aminohex-5-ynoic acid,an antimetabolite from Cortinarius claricolor var. Tenuipes

Screening for antimetabolites in edible mushrooms showed that the hot water extract of fruiting bodies of Cortinarius claricolor var. tenuipes strongly inhibited the growth of Bacillus subtilis B-50 in a chemically defined minimal medium. 2(S)-Aminohex-5-ynoic acid was isolated as an active compound.     

γ-l-Glutamyl-l-pipecolic acid in Gleditsia caspica

y-l-Glutamyl-l-pipecolic acid has been isolated from seeds of Gleditsia caspica (L.) Desf. Proof of its structure was obtained by chromatographic and spectroscopic examination of the natural product and its hydrolytic products. The new compound is the first example of a naturally occurring γ-glutamyl imino acid.     

Tetrahydrolathyrine: A new amino acid from seeds of Lonchocarpus costaricensis

A new non-protein amino acid, tetrahydrolathyrine (2(S)-3(2-amino-1,4,5,6- tetrahydropyrimidin-4-yl)alanine), has been isolated from seeds of Lonchocarpus costaricensis.     

海藻非蛋白质氨基酸的研究进展

海藻非蛋白质氨基酸是海藻中一类重要的生物活性物质,大多具有清热、解毒、驱虫、降血压、防癫痫等功能,本文主要对海藻非蛋白质氨基酸的概念、分类、生物合成、生物功能及其应用、检测分析、分离提取等做一概述,为更好的开发利用这类生物活性物质提供参考.     

Erythro-γ-hydroxyhomo-L-arginine: An amino acid from seed of Lonchocarpus costaricensis, and its preferential interaction with borate

A new non-protein amino acid, erythro-γ-hydroxyhomo-L-arginine has been isolated from seed of Lonchocarpus costaricensis by exploiting its property of interacting with borate ions. For structural comparisons, threo-γ-hydroxyhomo-L-arginine was isolated from seed of Lathyrus tingitanus and erythro-γ-hydroxyarginine from Vicia unijuga by novel procedures. The reasons for the interaction of borate with the erythro- but not the threo-forms of these amino acids are discussed.     

Distribution of α-amino-β-methylaminopropionic acid in Cycas

α-Amino-β-methylaminopropionic acid, previously isolated from seeds of Cycas circinalis, has now been identified either free or bound in all th     

Acide 2(R)-amino-3-butenoique (vinylglycine) dans les carpophores de Rhodophyllus nidorosus

2(R)-amino-3-butenoic acid (vinylglycine), the simplest β,γ-unsaturated α-amino acid, has been isolated from the mushroom Rhodophyllus nidorosus (Fr.) Quél. The amino acid occurs as partly racemized d-form. The structure has been confirmed by comparison with synthetic material.     

2(S),4(R)-4-(β-d-Galactopyranosyloxy)-4-isobutyl-glutamic acid: A new amino acid in Reseda odorata

2(S),4(R)-4-(β-d-Galactopyranosyloxy)-4-isobutylglutamic acid (I) has been isolated from the flowers of Reseda odorata, wherein it occurs in substantial quantity. Hydrolysis of I gives d-galactose, 2(S),4(R)-4-hydroxy-4-isobutylglutamic acid (II) and 3(R),5(S)-3-hydroxy-3-isobutyl-2-pyrrolidone-5-carboxylic acid (III) and its treatment with nitrous acid yields a galactoside of a non-nitrogenous hydroxy acid lactone (IV). The structures of I and its degradation products are supported by PMR, ¹³C-NMR and other spectroscopic methods. ¹³C-NMR spectroscopy of the model compound 2-(β-d-galactopyranosyloxy)isobutyric acid confirmed the structure of the natural product. The S- (or l-) configuration at C(2) in the amino acid moiety of I has been established by the use of the Clough—Lutz—Jirgenson rule and the R-configuration at C(4) of the same unit has been assigned tentatively. I represents the first example of a glycoside of a higher plant amino acid in which the carbohydrate residue is linked to an aliphatic hydroxy group.     

Homoserine in seedlings of the tribe vicieae of the leguminosae

Young seedlings of 10 subspecies and varieties of Pisum all accumulated high levels of homoserine, as did also Lathyrus latifolius seedlings. There was less in L. odoratus, and little or none in Cicer arietinum, Lens Culinaris, Vicia faba, and V. sativa seedlings.     

The co-occurrence of two diastereoisomers of 2,3-diaminobutanoic acid in root nodule hydrolysates of Lotus tenuis

The non-protein amino acid 2, 3-diaminobutanoic acid has been identified in the root nodules of Lotus tenuis inoculated with Rhizobium strain NZP2213. The co-occurrence of this compound in two diastereoisomeric forms was established by comparative GC retention time measurements on a Chirasil—Val capillary column.