1470-99-1Relevant articles and documents
Preparation method of Mitiglinide calcium intermediate
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Paragraph 0036-0044, (2018/11/22)
The invention relates to a preparation method of a Mitiglinide calcium intermediate. The method comprises the following steps: under nitrogen protection, adding tetrahydrofuran and zinc chloride intoa reactor in sequence for stirring, adding potassium borohydride one hour later, stirring for two hours, then adding cis-hexahydrophthalimide, carrying out a stirring reaction for two hours, adding asmall amount of concentrated sulfuric acid, slowly raising the temperature, heating to carry out a refluxing reaction for two hours, adding methylbenzene, slowly distilling until the internal temperature is about 94 DEG C, carrying out a refluxing reaction for three hours, continuously raising the temperature and distilling until the internal temperature is about 105 DEG C, stopping distillation,cooling below 30 DEG C, slowly dropwise adding 15% hydrochloric acid, after dropwise adding, raising the temperature and distilling until the internal temperature is about 107 DEG C, cooling below 30DEG C, dropwise adding 30% sodium hydroxide to adjust the pH value to be 13 to 14, and carrying out steam distillation and methylbenzene extraction drying to obtain cis-hexahydroisoindoline.
Efficient catalytic hydrogenation of N-unsubstituted cyclic imides to cyclic amines
Maj, Anna M.,Suisse, Isabelle,Pinault, Nathalie,Robert, Nicolas,Agbossou-Niedercorn, Francine
, p. 2621 - 2625 (2015/04/14)
The hydrogenation of N-unsubstituted cyclic imides to the corresponding cyclic amines has been performed selectively with heterogeneous catalysts obtained from rhodium and molybdenum carbonyl precursors. Various substrates were reduced in good to high yields and selectivities. Platinum-based catalysts also proved to be efficient. Furthermore, gram-scale experiments were performed and the catalysts could be recycled.
Enantioselective biocatalytic oxidative desymmetrization of substituted pyrrolidines
Koehler, Valentin,Bailey, Kevin R.,Znabet, Anass,Raftery, James,Helliwell, Madeleine,Turner, Nicholas J.
supporting information; body text, p. 2182 - 2184 (2010/06/18)
"Chemical Equation Presented" Center stage: Additions of nitrogen-centered radicals to cyanamide compounds provided the first radical synthesis of aromatic polycyclic guanidine derivatives (see scheme). Modular assembly of the substrates allows for a rapid increase of the molecular complexity of scaffolds, which have potential applications for medicinal chemistry.
A practical and efficient procedure for reduction of carboxylic acids and their derivatives: use of KBH4-MgCl2
Qiu, You-Chun,Zhang, Fu-Li,Zhang, Chun-Nian
, p. 7595 - 7598 (2008/03/14)
The use of KBH4-MgCl2 to reduce carboxylic acids and their derivatives to the corresponding alcohols or the respective reduced products is described. Methyl (S)-3,4-O-isopropylidene-3,4-dihydroxy butanoate 2 used as a reference substrate was reduced with KBH4 and MgCl2 in 1:1 mol ratio to (S)-1,2-O-isopropylidene-1,2,4-butanetriol 1.
Asymmetric desymmetrization of meso-pyrrolidine derivatives by enantiotopic selective C-H hydroxylation using (salen)manganese(III) complexes
Punniyamurthy,Katsuki, Tsutomu
, p. 9439 - 9454 (2007/10/03)
Chiral (salen)manganese(III) complexes 1 catalyzed the asymmetric desymmetrization of N-protected meso-pyrrolidine derivatives 3, 6-8, 15 and 18 by enantiotopic selective C-H oxidation in the presence of terminal oxidant iodosylbenzene. The oxidation occurred chemoselectively at the carbon α to the nitrogen atom to afford optically active hydroxypyrrolidine derivatives 9, 11, 13, 16, 19 and 21 that were further oxidized to chiral lactams with Jones reagent. The N-protecting groups of the meso-pyrrolidine derivatives have notable effect on the enantioselectivity.
Bis-penicillanoyloxy-alkanes
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, (2008/06/13)
The present invention relates to hitherto unknown esters of the below formula I, to salts of the esters of formula I with pharmaceutically acceptable acids, to methods for producing said new compounds, to pharmaceutical compositions containing said new compounds, and to methods of treating patients suffering from infectious diseases using said new compounds. The compounds of the invention, which are valuable in the human and veterinary practice, have the formula I STR1 in which R1 and R2 represent the same or different substituents, and each represents hydrogen or lower alkyl; A represents a carbon chain having from 5 to 8 carbon atoms, in which optionally an oxygen or a sulphur atom can be substituted for a methylene group; or the grouping STR2 represents a bicyclic system containing from 5 to 10 carbon atoms, or a bicyclic system containing from 4 to 9 carbon atoms, in which optionally an oxygen or a sulphur atom is substituted for a methylene group; or the grouping STR3 represent a spirocyclic system containing from 7 to 10 carbon atoms; R3 represents hydrogen or lower alkyl, halogen substituted lower alkyl, and unsubstituted and substituted aryl and aralkyl. The esters of the present invention are absorbed efficiently when given orally and are non-toxic when given parenterally. After the absorption the esters are converted to the corresponding penicillanic acids by enzymatic hydrolysis. Furthermore, these esters are chemically more stable then the corresponding free acids.
