10602-37-6Relevant academic research and scientific papers
TOTAL SYNTHESIS OF (+/-)-THIOLACTOMYCIN
Wang, Chia-Lin J.,Salvino, J. M.
, p. 5243 - 5246 (1984)
We have completed the first total synthesis of (+/-)-thiolactomycin by a five-step procedure in 10percent overall yield starting from ketoester 6.The key step involves addition of dianion 3 to 3-ethoxy-2-methyl-2-propenal.The resulting aldehyde 11 was then converted into (+/-)-thiolactomycin.
ULTRAPURE 4-METHYLPYRAZOLE
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Page/Page column 2; 3, (2008/06/13)
Disclosed is an ultrapure 4-methylpyrazole containing less than 0.1% pyrazole and containing less than 10 ppm each of hydrazine and nitrobenzaldehyde. The ultrapure 4-methylpyrazole is prepared by a novel process so that less than 0.01% of ethylvinyl ether is present.
ULTRAPURE 4-METHYLPYRAZOLE
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Page/Page column 8, (2008/06/13)
Disclosed is an ultrapure 4-methylpyrazole containing less than 0.1% pyrazole and containing less than 10 ppm each of hydrazine and nitrobenzaldehyde. The ultrapure 4-methylpyrazole is prepared by a novel process so that less than 0.01% of ethylvinyl ether is present.
Nitropyrazoles: XII. Transformations of the 4-methyl group in 1,4-dimethyl-3,5-dinitropyrazole and cyclization of the transformation products
Zaitsev,Dalinger,Starosotnikov,Kachala,Strelenko,Shkineva,Shevelev
, p. 1507 - 1515 (2007/10/03)
A preparative procedure for the synthesis of 1,4-dimethyl-3,5- dinitropyrazole by nitration of 1,4-dimethylpyrazole was developed. The reaction of 1,4-dimethyl-3,5-dinitropyrazole with dimethoxymethyl-(dimethyl)amine (N,N-dimethylformamide dimethyl acetal) gave (E)-N,N-dimethyl-2-(1-methyl-3,5- dinitropyrazol-4-yl)ethenylamine. Acid hydrolysis of the latter afforded (1-methyl-3,5-dinitropyrazol-4-yl)acetaldehyde, and the reaction with sodium nitrite in hydrochloric acid led to formation of 2-hydroxymino-2-(1-methyl-3,5- dinitropyrazol-4-yl)acetaldehyde. The corresponding O-methyloxime and phenylhydrazone reacted with K2CO3 to give 6-methyl-4-nitropyrazolo[4,3-d]isoxazole-3-carbaldehyde O-methyloxime and 1-methyl-3-nitro-4-(2-phenyl-2H-1,2,3-triazol-4-yl)pyrazol-5-ol, respectively. Treatment of (1-methyl-3,5-dinitropyrazol-4-yl)-acetaldehyde with benzenediazonium chloride gave (1-methyl-3,5-dinitropyrazol-4-yl)acetaldehyde phenylhydrazone which underwent intramolecular cyclization with replacement of the 5-nitro group by the action of K2CO3 in acetonitrile; in the reaction with K2CO3 in ethanol, the 5-nitro group was replaced by ethoxy.
A Concise Synthesis of the Octalactins
O'Sullivan, Paul T.,Buhr, Wilm,Fuhry, Mary Ann M.,Harrison, Justin R.,Davies, John E.,Feeder, Neil,Marshall, David R.,Burton, Jonathan W.,Holmes, Andrew B.
, p. 2194 - 2207 (2007/10/03)
The total synthesis of octalactins A and B has been achieved in 15 steps (longest linear sequence) and 10% overall yield from commercially available materials. Key steps include the Paterson-Aldol reaction for the rapid assembly of the carbonate 46, methylenation of 46 and subsequent Claisen rearrangement of the corresponding alkenyl-substituted cyclic ketene acetal to provide the core unsaturated medium-ring lactone 47, and the use of enzyme-mediated acetate deprotection in the presence of a medium-ring lactone.
CONDENSATION OF o-PHENYLENE DIAMINE AND SUBSTITUTED ACROLEINS TO FORM MACROHETEROCYCLES
Yatluk, Yu. G.,Suvorov, A. L.
, p. 316 - 320 (2007/10/02)
The reaction of o-phenylene diamine with β-alkoxy-, β-dimethylamino-, and β-acetoxy-α-alkyl- or α-arylacroleins has been studied.A new synthesis of 7,16-diaryldihydrodibenzo-tetraazaannulenes was developed, and the syntheses of 5,14 dihydrodibenzoteraazaannulene and 7,16-dialkyldihydrodibenzotetraazaannulenes were improved. 5,14-Dihydrodibenzotetraazaannulenes were synthesized with various substituents in the benzene rings and at possitions 7 an 16.
Preparation of acetals of malonaldehyde
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, (2008/06/13)
Acetals of malonaldehyde are prepared by reacting an orthoester with a vinyl ether in the presence of a catalytic amount of FeCl3. The malonaldehyde acetals obtainable by the process according to the invention are valuable intermediates in the preparation of dyes, crop protection agents and drugs.
Chemistry of enol ethers. LI. Reaction of vinyl silyl ethers with orthoformic esters
Makin, S. M.,Kruglikova, R. I.,Popova, T. P.,Tagirov, T. K.
, p. 630 - 634 (2007/10/02)
The silyl ethers of enolic forms of ketones react with orthoformates in the presence of zinc chloride at catalyst to form β-ketoacetals.The analogous reaction with the silyl ethers of enolic forms of aldehydes leads to the formation of the tetraacetals of 1,3-dialdehydes.
Process for preparing substituted 2,4-diaminopyrimidines and isoxazole intermediate
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, (2008/06/13)
A process for the preparation of 2,4-diamino-5-benzylpyrimidines by reacting 4-bromomethylisoxazole with an aromatic compound of the formula STR1 wherein R, R1 and R2 are hydrogen, lower alkoxy and lower alkyl, AND SUBSEQUENTLY TREATING THE REACTION PRODUCT WITH A GUANIDINE SALT, IS DESCRIBED.
Derivatives of 3-carboxy pyrid-2-ones
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, (2008/06/13)
Novel compounds belonging to the class of 1-substituted benzylpyrid-2-one-4,6-dialkyl and 4,5,6-trisubstituted-3-carboxylic acids, amides, esters and physiologically acceptable salts. These compounds possess biological activity and in particular are gametocides and plant growth regulators. Novel 1-substituted benzyl-3-cyano-4,5,6-trisubstituted pyrid-2-ones are also disclosed as intermediates.
