Ring Cleavage Reactions of Methyl α-D-Allopyranoside Derivatives with Phenylboron Dichloride and Triethylsilane
نویسندگان
چکیده
منابع مشابه
Ring cleavage reactions of methyl α-D-allopyranoside derivatives with phenylboron dichloride and triethylsilane.
In the course of our studies on the regioselective carbon-oxygen bond cleavage of the benzylidene acetal group of hexopyranosides with a reducing agent, we found that a combination of a Lewis acid and a reducing agent triggered a ring-opening reaction of the pyranose ring of methyl α-D-allopyranosides. The formation of an acyclic boronate ester by the attachment of a hydride ion at C-1 indicate...
متن کاملSynthesis and reactions of large-ring spirodienone calixarene derivatives
The isomerism of the polyspirodienone derivatives of the large-ring p-fertbutylcalix[n]arenes (n=5,6,8) is analyzed. Monoand polyspirodienone calix[n]arene derivatives were prepared by mild oxidation of the respective calix[n]arenes and the obtained products were characterized. Reactions of the monospirodienone derivatives with hydrazines and their rearrangements to xanthenocalixarenes are desc...
متن کاملRing Cleavage of Some Bicylic Compounds Derived from 1,2,4-Triazine
Ring cleavage occurred when 1,2,4-triazino-1,2,4-triazines (3), (4) and (5) were treated with concentrated hydrochloric acid to yield N-substituted triazines (7) and (8). These confirm the given configuration assigned to the isomeric triazinotriazines. 6-Methyl-2-phenyl-7H-oxazolo [3,2-b][1,2,4]-triazin-7-one (9) underwent ring cleavage on treatment with sodium alkoxide to afford 3-alkoxy-1...
متن کاملThe specificity of S-adenosylmethionine derivatives in methyl transfer reactions.
The preparation, purification, and analysis of a variety of new sulfonium derivatives of methionine is reported. Deamination of S-adenosyl-L-methionine with nitrous acid yielded, depending on experimental conditions, S-adenosyl L-(Z-hydroxy-4-methylthio)butyric acid or S-inosyl-L-(Z-hydroxy 4 methylthio)butyric acid. S-Inosyl L methionine was obtained by enzymatic deamination of S-adenosyl-Lhom...
متن کاملThe acid-mediated ring opening reactions of α-aryl-lactams.
4-Aryl-azetidin-2-ones (β-lactams) undergo ring opening with triflic acid to give cinnamamides which, in benzene, react further to give 3-aryl-3-phenyl-propionamides. Prolonged reaction times in benzene give 3,3-diphenyl-propionamide via an aryl/phenyl exchange. Lactams of ring size 7 and higher also ring open, but only 7- and 8-membered rings give pure diphenylalkylamides. AlCl(3) only ring op...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Molecules
سال: 2011
ISSN: 1420-3049
DOI: 10.3390/molecules161210303