2049-70-9Relevant articles and documents
Synthesis and mass spectra of rearrangement bio-signature metabolites of anaerobic alkane degradation via fumarate addition
Chen, Jing,Zhou, Lei,Liu, Yi-Fan,Hou, Zhao-Wei,Li, Wei,Mbadinga, Serge Maurice,Zhou, Jing,Yang, Tao,Liu, Jin-Feng,Yang, Shi-Zhong,Wu, Xiao-Lin,Gu, Ji-Dong,Mu, Bo-Zhong
, (2020/05/01)
Metabolite profiling in anaerobic alkane biodegradation plays an important role in revealing activation mechanisms. Apart from alkylsuccinates, which are considered to be the usual biomarkers via fumarate addition, the downstream metabolites of C-skeleton rearrangement can also be regarded as biomarkers. However, it is difficult to detect intermediate metabolites in both environmental samples and enrichment cultures, resulting in lacking direct evidence to prove the occurrence of fumarate addition pathway. In this work, a synthetic method of rearrangement metabolites was established. Four compounds, namely, propylmalonic acid, 2-(2-methylbutyl)malonic acid, 2-(2-methylpentyl)malonic acid and 2-(2-methyloctyl)malonic acid, were synthesized and determined by four derivatization approaches. Besides, their mass spectra were obtained. Four characteristic ions were observed at m/z 133 + 14n, 160 + 28n, 173 + 28n and [M - (45 + 14n)]+ (n = 0 and 2 for ethyl and n-butyl esters, respectively). For methyl esterification, mass spectral features were m/z 132, 145 and [M - 31]+, while for silylation, fragments were m/z 73, 147, 217, 248, 261 and [M - 15]+. These data provide basis on identification of potential rearrangement metabolites in anaerobic alkane biodegradation via fumarate addition.
A practical chemoenzymatic synthesis of (R)-isovaline based on the asymmetric hydrolysis of 2-ethyl-2-methyl-malonamide
Nojiri, Masutoshi,Yoshida, Fumi,Hirai, Yoshinori,Nishiyama, Akira,Yasohara, Yoshihiko
, p. 1 - 5 (2015/03/31)
(R)-Isovaline has potential applications in drug development, and therefore the development of an efficient method for the production of (R)-isovaline is desired. Herein we have investigated the asymmetric hydrolysis of 2-ethyl-2-methyl-malonamide into (S)-2-ethyl-2-methyl-malonamic acid, a useful synthetic intermediate in the production of (R)-isovaline, using CsAM, which is a recombinant amidase originally derived from Cupriavidus sp. KNK-J915. The produced (S)-2-ethyl-2-methyl-malonamic acid (98.6% ee) could be easily converted into (R)-isovaline by the Hofmann rearrangement. Starting from diethyl 2-methylmalonate, we obtained (R)-isovaline (99.1% ee) in 58.6% yield over eight steps, including the CsAM-catalyzed asymmetric hydrolysis of 2-ethyl-2-methyl-malonamide.
Effect of supramolecular inclusion on the 1,2-rearrangement of free radicals
Chen, Ying,Kervio, Eric,Retey, Janos
, p. 552 - 558 (2007/10/03)
The free radicals 3-ethoxy-2-(ethoxycarbonyl)-3-oxopropyl (1′) and 3-ethoxy-2-(ethoxycarbonyl)-2-methyl-3-oxopropyl (2′) were generated by photolysis of perester precursors in i) hexane solution, ii) in the presence of β-cyclodextrin, and iii) in NaY zeolite. While free radicals in solution are reluctant to rearrange, they do so when encapsulated in β-cyclodextrin or NaY zeolite. The coenzyme-B12-dependent enzymic rearrangement of methylmalonyl-CoA to succinyl-CoA could be mimicked by photochemical generation of an analogue of the putative intermediate radical in a molecular container.