Chemistry

Advances in Carbohydrate Chemistry, Vol. 13 by M. L. (editor) Wolfrom

By M. L. (editor) Wolfrom

Show description

Read or Download Advances in Carbohydrate Chemistry, Vol. 13 PDF

Similar chemistry books

Radical Reactions in Aqueous Media (RSC Green Chemistry Series, Volume 6)

Chemists at the moment are relocating clear of unstable, environmentally damaging, and biologically incompatible natural solvents. With its good value, prepared availability, and potential to take away environmentally unfriendly by-products, water is an seen alternative. fresh advances in loose radical chemistry in water have multiplied the flexibility and adaptability of homolytic carbon-hydrogen, carbon-carbon, carbon-halogen, carbon-nitrogen bond formations in aqueous media.

The Chemistry of Antitumour Agents

Walter C. J. ROSS Emeritus Professor, college of London To paraphrase a press release made via Howard E. Skipper a long time in the past, 'We melanoma chemotherapists have usually exploited and overworked our chemist colleagues and so they were with ease forgotten at award giving times'. This ebook is an try to rectify this and spotlight the contribution of the chemist in enhancing the constitution of varied kinds of agent to reinforce their effectiveness as inhibitors of the expansion of neoplastic tissues.

Additional resources for Advances in Carbohydrate Chemistry, Vol. 13

Sample text

Leipaig), 109, 65 (1924). Helferich, H. E. Scheiber, R. Streeck and V. Vorsate, A n n . , 618,211 (1935). Pigmttn, J . Research Null. Bur. Standards, 26. 197 (1941). FORMATION AND CLEAVAGE O F OXYGEN RINGS I N SUGARS 31 faster than methyl a-D-glucopyranoside (XVIII); this is presumably because, in thc favored conformation, the aglycon of the former compound assumes the more exposed equatorial position. g6However, it seems more reasonable to assume that the relative instability of these a-Danomers may result from the presence of large, axial substituents (phenyl and glycosyl rings) in the otherwise quite stable C l conformation.

77) W. G. Dauben and K . S. Pitzer, in “Steric Effects in Organic Chemistry,” M. S. , New York, N. , 1956, p. 1. (78) H. C. Brown, J . Chem. ,1248 (1956); Abstracts Papers A m . Chem. S O C . , 132, 3D (1957). (79) W. Klyne, in “Progress in Stereochemistry,” W. , Butterworths Scientific Publications, London, 1954, Vol. 1, p. 72. 26 F. SHAFIZhDEH cause of (a) the distortion of the tetrahedral valency angle or (b) the presence of eclipsed bonds; whereas the strain in the well-staggered, chair conformation of six-membered rings originates from the non-bonded interactions of the axial groups.

Edward, Chem. & Znd. (London), 1102 (1955). (97) E. Fischer and K. , 42,1476 (1909). (98) W. Schneider, J. Sepp and 0. , 61, 220 (1918). (99) C. B. Piirves, J . A m . Chem. , 61, 3627 (1929). (100) E. Pacsu and E. J. , J . A m . Chem. ,61, 1450, 1930 (1939). (101) W. Schneider and J. , 49,2054 (1916). (102) J. W. Green and E. Pacsu, J . A m . Chem. , 69, 1205 (1937). 32 F. 5% yield of D-glucose a t the point when the change in optical rotation indicates an 85 % completion of hydrolysis. Other products formed are ethyl l-deoxyl-thio-cr-D-glucopyranosideand its p-D anomer, as well as a small proportion of the less stable ethyl l-deoxy-l-thio-/3-n-glucofuranoside.

Download PDF sample

Rated 4.65 of 5 – based on 49 votes