Enzyme-catalysed hydrolysis of dimethyl 7-hydroxy-3,3-dimethyl-2,4-dioxabicyclo[3.3.0]octane-6,8-dicarboxylate and a novel synthesis of neplanocin A

1992 ◽  
pp. 2245 ◽  
Author(s):  
Edward J. Hutchinson ◽  
Stanley M. Roberts ◽  
Andrew J. Thorpe
Keyword(s):  
Neplanocin A ◽  
Novel Synthesis ◽  
Hydrolysis Of

ChemInform Abstract: Novel Synthesis Method of Hydroxyapatite Whiskers by Hydrolysis of α-Tricalcium Phosphate in Mixtures of Water and Organic Solvent.

ChemInform ◽  
2010 ◽  
Vol 30 (46) ◽  
pp. no-no
Author(s):  
Atsushi Nakahira ◽  
Kiyoko Sakamoto ◽  
Shunro Yamaguchi ◽  
Motoki Kaneno ◽  
Shinichi Takeda ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Tricalcium Phosphate ◽  
Synthesis Method ◽  
Novel Synthesis ◽  
Hydrolysis Of

Direct Preparation of 1,2:3,5-Di-O-cyclohexylidene-α-D-xylofuranose from Corncobs and Its Conversion to 1-O-Acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose

1994 ◽  
Vol 59 (8) ◽  
pp. 1884-1888 ◽  
Author(s):  
Mirjana Popsavin ◽  
Velimir Popsavin ◽  
Nada Vukojevic ◽  
Dušan Miljković
Keyword(s):  
Acid Hydrolysis ◽  
Hydroxyl Group ◽  
Partial Acid Hydrolysis ◽  
Novel Synthesis ◽  
Direct Preparation ◽  
Acid Methanolysis ◽  
Hydrolysis Of ◽  
Mild Acid

A novel synthesis of 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose (I) has been described starting from 1,2:3,5-di-O-cyclohexylidene-α-D-xylofuranose (II), obtained directly from the crude xylose syrup originated from corncobs. Partial acid hydrolysis of II gave 1,2-O-cyclohexylidene-α-D-xylofuranose (III). Selective benzoylation of primary C-5 hydroxyl group of III followed by tosylation of C-3 hydroxyl group afforded IV in an overall yield of 67%. Mild acid methanolysis of IV gave the corresponding methyl xylofuranosides V which were further benzoylated to afford 2,5-di-O-benzoyl derivatives VI in 65% yield. Solvolysis of VI in 95% DMF gave a mixture of 2,5- and 3,5-di-O-benzoylribofuranosides VII, which were subsequently converted into the corresponding tribenzoates VIII. An acetolysis of VIII afforded I in an overall yield of 96% related to VI.

Novel synthesis of Cu2O nano cubes derived from hydrolysis of Cu nano powder and its high catalytic effects

2007 ◽  
Vol 449-451 ◽  
pp. 817-820 ◽  
Author(s):  
Y.R. Uhm ◽  
J.H. Park ◽  
W.W. Kim ◽  
M.K. Lee ◽  
C.K. Rhee
Keyword(s):  
Nano Powder ◽  
Novel Synthesis ◽  
Catalytic Effects ◽  
Hydrolysis Of

Novel Synthesis Method of Hydroxyapatite Whiskers by Hydrolysis of alpha-Tricalcium Phosphate in Mixtures of Water and Organic Solvent

2004 ◽  
Vol 82 (8) ◽  
pp. 2029-2032 ◽  
Author(s):  
Atsushi Nakahira ◽  
Kiyoko Sakamoto ◽  
Shunro Yamaguchi ◽  
Motoki Kaneno ◽  
Shinichi Takeda ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Tricalcium Phosphate ◽  
Synthesis Method ◽  
Novel Synthesis ◽  
Hydrolysis Of

scholarly journals Formation of Calcium-Deficient Hydroxyapatite via Hydrolysis of Nano-Sized Pure α-Tricalcium Phosphate

2015 ◽  
Vol 1117 ◽  
pp. 201-204 ◽  
Author(s):  
Linda Vecbiskena ◽  
Karlis Agris Gross ◽  
Una Riekstina ◽  
C.K. Thomas Yang
Keyword(s):  
Phase Composition ◽  
Tricalcium Phosphate ◽  
Particle Shape ◽  
Solvent Water ◽  
Novel Synthesis ◽  
Freeze Dried ◽  
Reaction With Water ◽  
Hydrolysis Of ◽  
Synthesis Approach ◽  
Shape And Size

Nano-sized pure α-tricalcium phosphate (α-TCP) fabricated by a novel synthesis approach shows great potential for a faster transformation into calcium-deficient hydroxyapatite (CDHA) than conventionally prepared α-TCP. In this work, amorphous tricalcium phosphate precursors were precipitated and treated with a solvent (water or ethanol), and dried (freeze-dried and oven-dried) before heating at 775 °C. Nanosized α-TCP powders were investigated for their phase composition and crystallinity, particle shape and size, reactivity and cellular biocompatibility. Reaction with water showed faster CDHA formation for freeze-dried powder, at 6 hours, compared to ethanol treated powders, whereas a higher biocompatibility was found for pure α-TCP.

An efficient synthesis of 6-(4-chlorophenyl)-2,2-dimethyl-7-phenyl-2,3-dihydro-1H-pyrrolizine, a key intermediate in the licofelone synthesis

2009 ◽  
Vol 74 (6) ◽  
pp. 1011-1022 ◽  
Author(s):  
Stanislav Rádl ◽  
Jan Stach ◽  
Josef Černý ◽  
Ondřej Klecán
Keyword(s):  
Double Bond ◽  
Acid Hydrolysis ◽  
Schiff Bases ◽  
Clinical Studies ◽  
Phase Iii ◽  
Efficient Synthesis ◽  
Reaction Conditions ◽  
Novel Synthesis ◽  
Solvent Systems ◽  
Hydrolysis Of

An efficient synthesis of 6-(4-chlorophenyl)-2,2-dimethyl-7-phenyl-2,3-dihydro-1H-pyrrolizine, a key intermediate for the synthesis of licofelone, an anti-inflammatory drug currently undergoing evaluation of the phase-III clinical studies, is described. The method is based on a novel synthesis of unstable 5-benzyl-3,3-dimethyl-3,4-dihydro-2H-pyrrole, which is then treated with 2-bromo-1-(4-chlorophenyl)ethan-1-one. 2,2-Dimethyl-5-phenylpent-4-ynal with benzylamines provides the corresponding Schiff bases. Migration of the C=N double bond in these N-(2,2-dimethyl-5-phenylpent-4-yn-1-ylidene)benzylamines into conjugation with the aromatic ring using various base/solvent systems was studied. Acid hydrolysis of the formed Schiff bases then provided 2,2-dimethyl-5-phenylpent-4-yn-1-amine and 2,2-dimethyl-5-phenylpenta-3,4-dien-1-amine; their ratio was influenced mainly by the reaction conditions. Cyclization of these amines using Ag or Au catalysts then led to 5-benzyl-3,3-dimethyl-3,4-dihydro-2H-pyrrole.

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