Selective Benzoylation of Methyl 6-Deoxy-α- and β-D-glucopyranosides

1973 ◽  
Vol 51 (19) ◽  
pp. 3272-3276 ◽  
Author(s):  
Yôtaro Kondo ◽  
Kiyoshi Miyahara ◽  
Naoki Kashimura
Keyword(s):  
Major Product ◽  
Hydroxyl Groups ◽  
Secondary Hydroxyl

Selective dimolar benzoylation of methyl 6-deoxy-α- and β-D-glucopyranosides yielded the 2,3-di-O-benzoate of the respective glucopyranoside as the major product in 61 and 29% yields. The orders of the reactivity of the secondary hydroxyl groups in α- and β-anomers were different, i.e., the order was 2-OH > 3-OH > 4-OH for the former and 3-OH > 2-OH > 4-OH for the latter.

Preparation of prednisolone‐appended α‐, β‐ and γ‐cyclodextrins: Substitution at secondary hydroxyl groups and in vitro hydrolysis behavior

2001 ◽  
Vol 90 (4) ◽  
pp. 493-503
Author(s):  
Hideki Yano ◽  
Fumitoshi Hirayama ◽  
Hidetoshi Arima ◽  
Kaneto Uekama
Keyword(s):  
Hydroxyl Groups ◽  
Secondary Hydroxyl ◽  
In Vitro Hydrolysis

Halosugar nucleosides. II. Iodination of secondary hydroxyl groups of nucleosides with methyltriphenoxyphosphonium iodide

1970 ◽  
Vol 35 (9) ◽  
pp. 2868-2877 ◽  
Author(s):  
Julien P. H. Verheyden ◽  
John G. Moffatt
Keyword(s):  
Hydroxyl Groups ◽  
Secondary Hydroxyl

Regioselectivity among six secondary hydroxyl groups: selective acylation of the least reactive hydroxyl groups of inositol

2012 ◽  
Vol 48 (18) ◽  
pp. 2448 ◽  
Author(s):  
Amol M. Vibhute ◽  
Adiyala Vidyasagar ◽  
Saritha Sarala ◽  
Kana M. Sureshan
Keyword(s):  
Hydroxyl Groups ◽  
Secondary Hydroxyl ◽  
Selective Acylation

Conversion of hydroxyl groups into bromo groups in carbohydrates with inversion of configuration

1981 ◽  
Vol 59 (2) ◽  
pp. 339-343 ◽  
Author(s):  
Björn Classon ◽  
Per J. Garegg ◽  
Bertil Samuelsson
Keyword(s):  
Elevated Temperature ◽  
Hydroxyl Groups ◽  
Secondary Hydroxyl ◽  
Reaction Proceeds ◽  
One Step ◽  
High Yields

A novel reagent system is described for the efficient, one-step transformation of hydroxyl groups in carbohydrates to bromodeoxy groups. The reaction proceeds with inversion of configuration. The reagent system consists of triphenylphosphine, tribromoimidazole, and imidazole in toluene at elevated temperature. The carbohydrate need not be soluble in toluene. The examples given include substitution of isolated primary and secondary hydroxyl groups in otherwise protected carbohydrates as well as disubstitution involving one primary and one secondary position in hexopyranosides. High yields are obtained in the replacement of hydroxyl by bromine in the 2-position of 3,4,6-protected methyl α-D-gluco- and -mannopyranosides.

Regioselective monophosphorylation of glycols containing primary and secondary hydroxyl groups

2000 ◽  
Vol 10 (1) ◽  
pp. 3-4 ◽  
Author(s):  
Edward E. Nifantiev ◽  
Mikhail K. Gratchev ◽  
Stephen F. Martin
Keyword(s):  
Hydroxyl Groups ◽  
Secondary Hydroxyl

Dimethyl sulfoxide as a solvent in the Williamson ether synthesis

1969 ◽  
Vol 47 (11) ◽  
pp. 2015-2019 ◽  
Author(s):  
Russel G. Smith ◽  
Alan Vanterpool ◽  
H. Jean Kulak
Keyword(s):  
Reaction Time ◽  
Dimethyl Sulfoxide ◽  
Butyl Alcohol ◽  
Major Product ◽  
Hydroxyl Groups ◽  
Reaction Products ◽  
Butyl Chloride ◽  
Butyl Ether ◽  
Ether Synthesis ◽  
Williamson Ether Synthesis

Using the conventional Williamson ether synthesis, n-butyl ether was prepared from sodium hydroxide, n-butyl alcohol, and n-butyl chloride using excess of the alcohol as solvent in 61% yield after 14 h reaction time. However, when the excess alcohol was replaced by dimethyl sulfoxide, the yield of ether rose to 95% with 9.5 h reaction time. Other primary alkyl chlorides exhibited similar behavior to n-butyl chloride, but secondary alkyl chlorides and primary alkyl bromides gave little etherification, elimination being the major reaction. Unreactive halides, such as vinyl chloride, phenyl bromide, and 2,4-dinitrobromobenzene, were not etherified in dimethyl sulfoxide. The reaction products obtained from aliphatic dichlorides depended upon the relative positions of the chlorine atoms. Secondary alcohols reacted to give ethers, but tertiary alcohols were very unreactive. Polyols generally gave high yields of ethers, the major product being that in which all but one of the hydroxyl groups became etherified. Under forcing conditions, however, completely etherified polyols could be obtained.

Preparation of prednisolone-appended α-, β- and γ-cyclodextrins: Substitution at secondary hydroxyl groups and in vitro hydrolysis behavior

2001 ◽  
Vol 90 (4) ◽  
pp. 493-503 ◽  
Author(s):  
Hideki Yano ◽  
Fumitoshi Hirayama ◽  
Hidetoshi Arima ◽  
Kaneto Uekama
Keyword(s):  
Hydroxyl Groups ◽  
Secondary Hydroxyl ◽  
In Vitro Hydrolysis

THE REACTIVITY OF CELLULOSE: III. THE NITRATION OF COTTON LINTERS ALTERNATELY WETTED WITH WATER AT VARIOUS TEMPERATURES AND DRIED, AND THE PROBABLE DISTRIBUTION OF THE NITRATE GROUPS

1959 ◽  
Vol 37 (2) ◽  
pp. 444-453 ◽  
Author(s):  
T. P. Yin ◽  
R. K. Brown
Keyword(s):  
Lead Tetraacetate ◽  
Hydroxyl Groups ◽  
Secondary Hydroxyl ◽  
Cotton Linters ◽  
Probable Distribution

Cotton linters alternately wetted at 0° or 25° and dried show progressively greater ease of nitration paralleling the number of wetting–drying cycles. The reverse is found to be true for linters wetted at 50°, 75°, or 100°. Analysis of the data obtained from lead tetraacetate oxidation of the nitrates favors the depressive concept of nitration and indicates that the observed changes in reactivity occasioned by the wetting–drying treatments are largely due to greater alterations in the accessibility of the primary rather than the secondary hydroxyl groups.

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