4554-16-9Relevant articles and documents
Synthesis, Molecular Structure, and Spectroscopical Properties of Alkenylphosphonic Derivatives. 1. Vinyl-, Propenyl-, (Bromoalkenyl)-, and (Cyanoalkenyl)phosphonic Compounds
Sainz-Diaz, C. I.,Galvez-Ruano, E.,Hernandez-Laguna, A.,Bellanato, J.
, p. 74 - 83 (1995)
Several vinyl-, propenyl-, (bromoalkenyl)-, and (cyanoalkenyl)phosphonate derivatives have been synthesized.The (2-cyanovinyl)phosphonates have been obtained with an important improvement in the yield (40percent versus 6percent).The separation of the E and Z isomers of the cyano derivatives and their hydrolysis to the corresponding phosphonic acids have been studied.The bromination and dehydrobromination of some alkenylphosphonic derivatives have also been studied.Spectroscopical studies from UV, IR, Raman, and 1H, 13C, and 31P NMR have been performed in most of these derivatives.The C=C/P=O ? conjugation exists but it is weak in all these compounds.Dipole moments and C=C/P=O conformational populations have been calculated theoretically by ab initio methods.The effect of the solvent polarity on the conformational population has been observed by IR spectroscopy disclosing two C=C/P=O conformers.Experimental and theoretical results have been compared, a high level of agreement has been found.
Method for efficiently synthesizing N-3-isooxazole tert-butyl carbamate
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Paragraph 0030; 0032, (2019/03/08)
The invention discloses a method for efficiently synthesizing N-3-isooxazole tert-butyl carbamate. The synthetic route comprises the following steps: brominating a compound A to obtain a compound B, and reacting the compound B and a compound C to obtain a compound D; and reacting the compound D and di-tert-butyl dicarbonate ester, thereby obtaining the compound E. The reaction formula is as shownin the specification. The process method for synthesizing 3-aminoisoxazole is simple in process, cheap and readily available in raw materials, simple and convenient in operation and extremely suitablefor large-scale industrial production, and has very wide industrial application prospects and market value.
Characterization of an indole-3-acetamide hydrolase from alcaligenes faecalis subsp. parafaecalis and its application in efficient preparation of both enantiomers of chiral building block 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid
Mishra, Pradeep,Kaur, Suneet,Sharma, Amar Nath,Jolly, Ravinder S.
, (2016/07/26)
Both the enantiomers of 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid are valuable chiral synthons for enantiospecific synthesis of therapeutic agents such as (S)-doxazosin mesylate, WB 4101, MKC 242, 2,3-dihydro-2-hydroxymethyl-1,4-benzodioxin, and N-[2,4-oxo-1,3-thiazolidin-3-yl]-2,3-dihydro-1,4-benzodioxin-2-carboxamide. Pharmaceutical applications require these enantiomers in optically pure form. However, currently available methods suffer from one drawback or other, such as low efficiency, uncommon and not so easily accessible chiral resolving agent and less than optimal enantiomeric purity. Our interest in finding a biocatalyst for efficient production of enantiomerically pure 2,3-dihydro-1,4-benzodioxin-2-carboxylic acid lead us to discover an amidase activity from Alcaligenes faecalis subsp. parafaecalis, which was able to kinetically resolve 2,3-dihydro-1,4-benzodioxin-2-carboxyamide with E value of >200. Thus, at about 50% conversion, (R)-2,3-dihydro-1,4-benzodioxin-2-carboxylic acid was produced in >99% e.e. The remaining amide had (S)-configuration and 99% e.e. The amide and acid were easily separated by aqueous (alkaline)-organic two phase extraction method. The same amidase was able to catalyse, albeit at much lower rate the hydrolysis of (S)-amide to (S)-acid without loss of e.e. The amidase activity was identified as indole-3-acetamide hydrolase (IaaH). IaaH is known to catalyse conversion of indole-3-acetamide (IAM) to indole-3-acetic acid (IAA), which is phytohormone of auxin class and is widespread among plants and bacteria that inhabit plant rhizosphere. IaaH exhibited high activity for 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which was about 65% compared to its natural substrate, indole-3-acetamide. The natural substrate for IaaH indole-3-acetamide shared, at least in part a similar bicyclic structure with 2,3-dihydro-1,4-benzodioxin-2-carboxamide, which may account for high activity of enzyme towards this un-natural substrate. To the best of our knowledge this is the first application of IaaH in production of industrially important molecules.
