1758-80-1Relevant articles and documents
Chemo-selective Rh-catalysed hydrogenation of azides into amines
Galan, M. Carmen,Ghirardello, Mattia,Ledru, Helene,Sau, Abhijit
supporting information, (2020/02/18)
Rh/Al2O3 can be used as an effective chemo-selective reductive catalyst that combines the mild conditions of catalytic hydrogenation with high selectivity for azide moieties in the presence of other hydrogenolysis labile groups such as benzyl and benzyloxycarbonyl functionalities. The practicality of this strategy is exemplified with a range of azide-containing carbohydrate and amino acid derivatives.
Chemical structure of cichorinotoxin, a cyclic lipodepsipeptide that is produced by Pseudomonas cichorii and causes varnish spots on lettuce
Komatsu, Hidekazu,Shirakawa, Takashi,Uchiyama, Takeo,Hoshino, Tsutomu
, p. 299 - 309 (2019/02/20)
Pseudomonas cichorii, which causes varnish spots on lettuce and seriously damages lettuce production during the summer season in the highland areas of Japan (e.g., Nagano and Iwate prefectures) was isolated. The structure of a toxin produced by this organism was analyzed based on the detailed evaluation of its 2D NMR and FABMS spectra, and this compound has not been reported previously. We propose the name cichorinotoxin for this toxin. In conjunction with the D or L configurations of each amino acid, which were determined by Marfey’s method, we propose the structure of cichorinotoxin to be as follows: 3-hydroxydecanoyl-(Z)-dhThr1-D-Pro2-D-Ala3-D-Ala4-D-Ala5-D-Val6-D-Ala7-(Z)-dhThr8-Ala9-Val10-D-Ile11-Ser12-Ala13-Val14-Ala15-Val16-(Z)-dhThr17-D-alloThr18-Ala19-L-Dab20-Ser21-Val22, and an ester linkage is present between D-alloThr18 and Val22 (dhThr: 2-aminobut-2-enoic acid; Dab: 2,4-diaminobutanoic acid). Thus, the toxin is a lipodepsipeptide with 22 amino acids. The mono- and tetraacetate derivatives and two alkaline hydrolysates, compounds A and B, were prepared. We discuss here the structure–activity relationships between the derivatives and their necrotic activities toward lettuce.
Preparation method of L-2,4-diaminobutyrate hydrochloride
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Paragraph 0020-0023, (2019/10/22)
The invention belongs to the technical field of organic chemistry, and discloses a preparation method of L-2,4-diaminobutyrate hydrochloride. The method includes the following steps that S1, L-glutamine is subjected to Boc protection under an alkaline condition to obtain a N-BOC-L-glutamine aqueous solution; S2, a saturated sodium hypochlorite solution is dropwise added into the N-Boc-L-glutamineaqueous solution obtained in the S1 for a degradation reaction, and a L-2-N-Boc-4-aminobutyric acid crude product solution is obtained; S3, the L-2-N-Boc-4-aminobutyric acid crude product solution iscondensed, the pH is adjusted with 2N hydrochloric acid, salt is removed with cation exchange resin, dilute ammonia water is used as an elution agent for elution, the eluent is condensed, concentratedhydrochloric acid is added for adjusting the pH of a concentrated solution, absolute ethyl alcohol is added, and after crystallization, filtering and drying, the L-2,4-diaminobutyrate hydrochloride is obtained. The method has the advantages that the synthetic route is short, operation is simple, three wastes pollution is less, the yield is high and the cost is low, and the method is an ideal scheme for industrial scale-up production.
COMPOSITIONS AND METHODS FOR THE TREATMENT OF BACTERIAL INFECTIONS
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Page/Page column 168, (2018/02/28)
Compositions and methods for the treatment of bacterial infections include compounds containing dimers of cyclic heptapeptides. In particular, compounds can be used in the treatment of bacterial infections caused by Gram-negative bacteria.
(S)-2-methyl-1,4,5,6-tetrahydromethylpyrimidine-4-carboxylic acid synthesis method
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Paragraph 0068; 0069; 0070, (2017/08/30)
The present invention relates to a (S)-2-methyl-1,4,5,6-tetrahydromethylpyrimidine-4-carboxylic acid synthesis method. According to the method, L-glutamine is used as a raw material, the alpha-amino of the L-glutamine is protected with a protection group, a decarbonylating agent is added, a Hofmann degradation reaction is performed to remove the carbonyl group attached to the remaining amino, the protection group is removed to obtain L-2,4-diaminobutyric acid, and finally the prepared L-2,4-diaminobutyric acid and trimethyl orthoacetate are subjected to a ring forming reaction to obtain the (S)-2-methyl-1,4,5,6-tetrahydromethylpyrimidine-4-carboxylic acid. Compared to the method in the prior art, the method of the present invention has the following characteristics that the chemical synthesis route is provided, the steps of the synthesis process are simple, the raw materials are easy to obtain, the product purity is high, and the method is suitable for large-scale industrial production.
Immunomodulatory peptides
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, (2014/12/12)
The invention relates to peptides derivatized with a hydrophilic polymer which, in some embodiments, bind to human FcRn and inhibit binding of the Fc portion of an IgG to an FcRn, thereby modulating serum IgG levels. The disclosed compositions and methods may be used in some embodiments, for example, in treating autoimmune diseases and inflammatory disorders. The invention also relates, in further embodiments, to methods of using and methods of making the peptides of the invention.
Catalyst functional group cooperativity in the amino acid-catalysed nitroaldol condensation reaction
Karadeniz, Leman,Astley, Stephen T.
, p. 3407 - 3415 (2013/09/23)
Several amino acids and their derivatives have been evaluated as organic catalysts for the nitroaldol reaction. It was found that when an unprotected amino group and an unprotected carboxylate group were present in the organocatalyst, both the nitroaldol reaction and subsequent elimination could occur to afford nitroalkenes from aromatic aldehydes and nitromethane. The best results were obtained by use of γ-amino acids derived from l-glutamine. It is suggested that the amino group is important for intermediate Schiff base formation and that the free carboxylate group facilitates the elimination step.
Structure and biosynthetic assembly of cupriachelin, a photoreactive siderophore from the bioplastic producer cupriavidus necator H16
Kreutzer, Martin F.,Kage, Hirokazu,Nett, Markus
experimental part, p. 5415 - 5422 (2012/05/20)
The bacterium Cupriavidus necator H16 produces a family of linear lipopeptides when grown under low iron conditions. The structural composition of these molecules, exemplified by the main metabolite cupriachelin, is reminiscent of siderophores that are excreted by marine bacteria. Comparable to marine siderophores, the ferric form of cupriachelin exhibits photoreactive properties. Exposure to UV light induces an oxidation of its peptidic backbone and a concomitant reduction of the coordinated Fe(III). Here, we report the genomics-inspired isolation and structural characterization of cupriachelin as well as its encoding gene cluster, which was identified by insertional mutagenesis. Based upon the functional characterization of adenylation domain specificity, a model for cupriachelin biosynthesis is proposed.
Isolation and characterization of peptide antibiotics LI-F04 and polymyxin B6 produced by Paenibacillus polymyxa strain JSa-9
Deng, Yang,Lu, Zhaoxin,Bi, Hua,Lu, Fengxia,Zhang, Chong,Bie, Xiaomei
experimental part, p. 1917 - 1923 (2012/05/19)
Paenibacillus polymyxa JSa-9 had been found to produce five cyclic LI-F type antibiotics which were released into culture medium in accordance with our previous report. In this study, another three kinds of antagonistic compounds were extracted from P. polymyxa JSa-9 cell pellets and (or) spores by methanol. Using high performance liquid chromatography (HPLC) method, two antagonistic fractions were separated and collected from the methanol extract. One showed inhibition against Escherichia coli and Staphylococcus aureus, while the other was active against Aspergillus niger and S. aureus. By means of electrospray ionization mass spectroscopy (ESI-MS), infrared spectroscopy (IR), and amino acid analysis, two kinds of compounds from fraction B with molecular masses of 901 and 915 Da were characterized as the linear lipopeptide analogs of antibiotics LI-F04a and LI-F04b, respectively. Another antimicrobial substance from fraction A could be attributed to polymyxin B6.
A new approach to the synthesis of selectively protected (2S)-1,2,4-triaminobutane derivatives
Treder, Adam P.,Walkowiak, Aleksandra,Zgoda, Wlodzimierz,Andruszkiewicz, Ryszard
, p. 2281 - 2283 (2007/10/03)
An efficient synthesis of selectively protected (2S)-1,2,4-triaminobutane from L-glutamic acid via (2S)-N4-benzyloxycarbonyl-2,4- diaminobutanamid is described. Georg Thieme Verlag Stuttgart.
