29475-64-7Relevant academic research and scientific papers
Preparation method of N-methylamino acid with optical configurations
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Paragraph 0033; 0034; 0035; 0040; 0041, (2017/08/29)
The invention belongs to the field of medicine synthesis, relates to a preparation method of N-methylamino acid with optical configurations and in particular relates to a preparation method of N-methylamino acid with an R configuration and an S configuration. The preparation method is shown in the description. According to the preparation method provided by the invention, the configurations of reactants are transformed to obtain the N-methylamino acid with corresponding opposite configurations, and the preparation method is suitable for commercial scale production.
Cyclombandakamines A1 and A2, Oxygen-Bridged Naphthylisoquinoline Dimers from a Congolese Ancistrocladus Liana
Lombe, Blaise Kimbadi,Bruhn, Torsten,Feineis, Doris,Mudogo, Virima,Brun, Reto,Bringmann, Gerhard
supporting information, p. 1342 - 1345 (2017/03/23)
Cyclombandakamines A1 (1) and A2 (2), both with an unprecedented pyrane-cyclohexenone-dihydrofuran sequence and six stereocenters and two chiral axes, are the first oxygen-bridged dimeric naphthylisoquinoline alkaloids. They were isolated from the leaves of an as yet unidentified Congolese Ancistrocladus species. Their stereostructures were established by spectroscopic, chemical, and chiroptical methods in combination with DFT and TDDFT calculations. They apparently originate from a cascade of oxidative cyclization reactions of open-chain naphthylisoquinoline dimers and exhibit significant antiprotozoal activities.
Foxo3a Inhibitors of Microbial Origin, JBIR-141 and JBIR-142
Kawahara, Teppei,Kagaya, Noritaka,Masuda, Yuichi,Doi, Takayuki,Izumikawa, Miho,Ohta, Kumiko,Hirao, Atsushi,Shin-Ya, Kazuo
supporting information, p. 5476 - 5479 (2015/11/18)
JBIR-141 (1) and JBIR-142 (2) were discovered as potent Foxo3a inhibitors that consist of three quite unique substructures, a 1-((dimethylamino)ethyl)-5-methyl-4,5-dihydrooxazole-4-carboxylic acid that is originated from Ala-Thr amino acid residues, a 3-acetoxy-4-amino-7-(hydroxy(nitroso)amino)-2,2-dimethylheptanoic acid, and an α-acyl tetramic acid fused with a 2-methylpropan-1-ol moiety. Their structures involving absolute configurations were determined by spectroscopic data, chemical degradation, anisotropy methods, and LC-MS analyses of diastereomeric derivatives. Compounds 1 and 2 exhibited specific inhibition against Foxo3a transcriptional activity with IC50 values of 23.1 and 166.2 nM, respectively.
Isolation and characterization of two novel antibacterial cyclic hexapeptides from streptomyces alboflavus 313
Ji, Zhiqin,Qiao, Gang,Wei, Shaopeng,Fan, Lixia,Wu, Wenjun
, p. 1567 - 1578 (2012/10/29)
Two novel cyclic hexapeptides, designated NW-G08 (1) and NW-G09 (2), were isolated from the fermentation broth of Streptomyces alboflavus 313. Their structures were elucidated on the basis of extensive spectroscopic analysis, MS experiments, and chemical
Cyclodepsipeptides, sesquiterpenoids, and other cytotoxic metabolites from the filamentous fungus Trichothecium sp. (MSX 51320)
Sy-Cordero, Arlene A.,Graf, Tyler N.,Adcock, Audrey F.,Kroll, David J.,Shen, Qi,Swanson, Steven M.,Wani, Mansukh C.,Pearce, Cedric J.,Oberlies, Nicholas H.
experimental part, p. 2137 - 2142 (2011/12/14)
Two new cyclodepsipeptides (1 and 2), two new sesquiterpenoids (3 and 4), and the known compounds guangomide A (5), roseotoxin S, and three simple trichothecenes were isolated from the cytotoxic organic extract of a terrestrial filamentous fungus, Trichothecium sp. The structures were determined using NMR spectroscopy and mass spectrometry. Absolute configurations of the cyclodepsipeptides were established by employing chiral HPLC, while the relative configurations of 3 and 4 were determined via NOESY data. The isolation of guangomide A was of particular interest, since it was reported previously from a marine-derived fungus.
Preparation of N-Z-protected N-methylated amino acids
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, (2008/06/13)
A process for preparing N-protected N-alkylated amino acids of the formula I: in which the substituents have the meanings stated in the description, comprises mixing a compound of the formula II with a solution of potassium tert-butanolate in a non-protic organic solvent, and subsequently adding a C1-2-alkyl halide.
Absolute configuration of aflastatin A, a specific inhibitor of aflatoxin production by Aspergillus parasiticus
Ikeda, Hiroyuki,Matsumori, Nobuaki,Ono, Makoto,Suzuki, Akinori,Isogai, Akira,Nagasawa, Hiromichi,Sakuda, Shohei
, p. 438 - 444 (2007/10/03)
Aflastatin A (1) is a specific inhibitor of aflatoxin production by Aspergillus parasiticus. It has the novel structure of a tetramic acid derivative with a long alkyl side chain. The absolute configurations of 29 chiral centers contained in I were chemically elucidated in this study. First, four small fragment molecules were prepared from I or its methyl ether (2), and their absolute structures were assigned as N-methyl-D-alanine, (2S,4R)-2,4-dimethyl-1,6-hexanediol dibenzoate, (R)-3-hydroxydodecanoic acid, and (R)-1,2,4-butanetriol tribenzoate. Next, an acyclic fragment molecule 3 with 13 chiral centers was obtained from I by NaIO4 oxidation, and its relative stereochemistry was elucidated by J-based configuration analysis. By analyzing coupling constants of 3J(H,H) and 2,3J(C,H) and ROE data, the relative configuration of 3 was verified. Finally, by further J-based configuration analysis using a fragment molecule 7 prepared from 2 with 28 chiral carbons, all relative configurations in the alkyl side chain of I were clarified. By connecting these relative configurations with the absolute configurations of first four fragment molecules, the absolute stereochemistry of 1 was fully determined.
Amino Acids, 4 - Enantioselective Synthesis of N-Substituted α-Amino Carboxylic Acids from α-Hydroxy Carboxylic Acids
Effenberger, Franz,Burkard, Ulrike,Willfahrt, Joachim
, p. 314 - 333 (2007/10/02)
With primary and secondary amines, the (S)-α-(trifluoromethylsulfonyloxy) carboxylates (S)-3 afford in an SN2 reaction the N-substituted (R)-α-amino carboxylates (R)-5, (R)-9, and (R)-12, resp.The rates of α-substituted ethyl propionates decrease in the order of the substituents triflate (3a) >> bromide (8a) > mesylate (7a) >= tosylate (7b) > chloride (8b); in the reactions with amines, decreasing reactivity affords increasing racemisation and elimination as a consequence of the more drastic conditions which are required
