Synthesis and taste properties of L-aspartyl-methylated 1-aminocyclopropanecarboxylic acid methyl esters
摘要:
Several isomers of L-aspartyl-1-aminocyclopropanecarboxylic acid methyl ester with methyl group substitutions on the cyclopropane ring were synthesized. Conformational analyses were carried out on these molecules using H-1 NMR and molecular modeling studies. Their taste properties are explained on the basis of our previously reported topochemical model for taste response.
The resolution of racemic 2-alkyl-1-aminocyclopropane-1-carboxylic acids
作者:Jack E. Baldwin、Robert M. Adlington、Bernard J. Rawlings、Richard H. Jones
DOI:10.1016/s0040-4039(00)61918-4
日期:1985.1
Practical procedures for the resolution of racemic modification of (1, 2)-and (1, 2)-1-amino-2-ethylcyclopropane-1-carboxylic acid ,,(1, 2)- and (1, 2)-1-amino-2-methylcyclopropane-1-carboxylic acid ,, and (1, 2)- and (1, 2)-1-amino-2-methylcyclopropane-1-carboxylic acid , are described; the structures as ,, and were confirmed by X-ray-crystallographic methods.
Our interest on engineering non-ribosomal synthetase responsible for SW-163 biosynthesis prompted us to determine the relative and absoluteconfiguration of antitumor cyclic depsipeptide SW-163s. We first isolated and identified SW-163 homologs D, F and G as known compounds UK-63598, UK-65662 and UK-63052, respectively. Both enantiomers of the unusual constitutive amino acid, N-methylnorcoromic acid
Norcoronatine and N-coronafacoyl-L-valine, phytotoxic analogues of coronatine produced by a strain of Pseudomonas syringae pv. glycinea
作者:Robin E. Mitchell
DOI:10.1016/s0031-9422(00)81049-3
日期:1985.1
that were isolated and identified were coronatine, the major component, and N -coronafacoyl- L -valine, which are both biologically active, and coronafacic acid which is inactive. In addition a new minor component was isolated and purified. Mass spectrometry indicated that this was an amide of coronafacic acid, bearing one less methylene group than coronatine. Mass spectral and NMR data, together with
<i>Escherichia coli</i> Allows Efficient Modular Incorporation of Newly Isolated Quinomycin Biosynthetic Enzyme into Echinomycin Biosynthetic Pathway for Rational Design and Synthesis of Potent Antibiotic Unnatural Natural Product
作者:Kenji Watanabe、Kinya Hotta、Mino Nakaya、Alex P. Praseuth、Clay C. C. Wang、Daiki Inada、Kosaku Takahashi、Eri Fukushi、Hiroki Oguri、Hideaki Oikawa
DOI:10.1021/ja902261a
日期:2009.7.8
straightforward and efficient means of preparing natural product analogs. The quinomycin family of nonribosomal peptides, including echinomycin, triostin A, and SW-163s, are important secondary metabolites imparting antibiotic antitumor activity via DNA bisintercalation. Previously we have shown the production of echinomycin and triostin A in E. coli using our convenient and modular plasmid system to
天然产物对包括病毒、微生物和肿瘤在内的广泛目标表现出令人印象深刻的活性。然而,它们的临床应用经常受到其稀缺性和不良毒性的阻碍。工程大肠杆菌不仅可以为基于质粒的药效团生物合成提供简单且易于扩展的有价值但难以获得的化合物的替代方法,而且还具有提供制备天然产物类似物的直接和有效方法的潜力。非核糖体肽的奎霉素家族,包括棘霉素、triostin A 和 SW-163s,是重要的次级代谢产物,通过 DNA 双嵌入赋予抗生素抗肿瘤活性。之前我们已经展示了棘霉素和曲奥斯汀 A 在大肠杆菌中的产生。使用我们方便的模块化质粒系统将这些异源生物合成途径引入大肠杆菌中。然而,我们尚未开发出一种能够在大肠杆菌中产生具有生物活性的非天然天然产物的新型生物合成途径。在这里,我们报告了负责 SW-163s 生物合成的新基因簇的鉴定,该基因簇涉及以前未知的 (+)-(1S, 2S)-去甲花酸的生物合成和通过迭代甲基化生成各
Mechanism of <i>S</i>-Adenosyl-<scp>l</scp>-methionine <i>C</i>-Methylation by Cobalamin-dependent Radical <i>S</i>-Adenosyl-<scp>l</scp>-methionine Methylase in 1-Amino-2-methylcyclopropanecarboxylic Acid Biosynthesis
C-methylation of SAM in the biosynthesis of 1-amino-2-methylcyclopropanecarboxylic acid. Here, we determined that the methylation product is (4″R)-4″-methyl-SAM. Furthermore, we found that the 5′-deoxyadenosyl radical generated by Orf29 abstracts the pro-R hydrogen atom from the C-4″ position of SAM to generate the radical intermediate, which reacts with methylcobalamin to give (4″R)-4″-methyl-SAM
自由基S-腺苷-l-甲硫氨酸 (SAM) 甲基化酶 Orf29在 1-氨基-2-甲基环丙烷甲酸的生物合成中催化SAM 的C-甲基化。在这里,我们确定甲基化产物是(4″ R )-4″-甲基-SAM。此外,我们发现Orf29产生的5′-脱氧腺苷自由基从SAM的C-4”位上夺取pro-R氢原子,生成自由基中间体,该自由基中间体与甲钴胺反应生成(4” R )-4” -甲基-SAM。因此,证实Orf29催化的C-甲基化在构型保留的情况下进行。