scholarly journals SYNTHESIS OF 1,2;3,4-DI-O-ISOPROPYLIDENE-6- O-[4-(1H-AZOL-1-YLMETHYL) PHENYL]- ¯-D-GALACTOPYRANOSE AND 1,2,3,4-TETRA-O-ACETYL-6- O-[4-(1H-AZOL-1- YLMETHYL)PHENYL]-¯-D-GLUCOPYRANOSE

2017 ◽  
Vol 17 (5) ◽  
pp. 122-128
Author(s):  
Z.P. Belousova ◽  
P.P. Purygin ◽  
A.P. Tyurin
Keyword(s):  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Secondary Hydroxyl ◽  
Primary Hydroxyl ◽  
Derivatives Of

Derivatives of D-galactose and D-glucose substituted for the primary hydroxyl group, which contain an aglycone azolylmethylphenyl fragments (for imidazole, 1,2,4-triazole, benzimidazole and benzotriazole) has been synthesized. Toprotect the secondary hydroxyl groups of monosaccharides acetyl and isopropylidene groups were used.

Assembly of Platinum Nanoparticles and Single-atom Bismuth for Selective Oxidation of Glycerol

2021 ◽  
Author(s):  
Ning Huang ◽  
Zihao Zhang ◽  
Yubing Lu ◽  
Jinshu Tian ◽  
Dong Jiang ◽  
...  
Keyword(s):  
Selective Oxidation ◽  
Platinum Nanoparticles ◽  
Single Atom ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Main Difficulty ◽  
Secondary Hydroxyl

Selective oxidation of the secondary hydroxyl group of glycerol to dihydroxyacetone (DHA) is an extremely challenging yet important reaction. The main difficulty is that three hydroxyl groups in glycerol are...

Revision of the structures of partially acylated derivatives of aldose diethyl dithioacetals

1980 ◽  
Vol 58 (13) ◽  
pp. 1365-1371 ◽  
Author(s):  
T. Bruce Grindley ◽  
Rathy Ponnampalam
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Current Work ◽  
Hydroxyl Group ◽  
Resonance Spectroscopy ◽  
Secondary Hydroxyl ◽  
Derivatives Of ◽  
Nuclear Magnetic

1H nuclear magnetic resonance spectroscopy is used to correct the structures of most of the known partially acylated derivatives of aldose diethyl dithioacetals which contain more than one acyl group. Previous work had suggested that the hydroxyl group on carbon-2 was the least readily acylated secondary hydroxyl group; current work indicates that it is among the most readily acylated. Evidence is presented which shows that the preferential methylation of aldose diethyl dithioacetals at O-2 is caused by the presence of the sulfur atoms.

scholarly journals Antioxidant activity of some coumarins / Antioxidačná activita niektorých kumarínov

2015 ◽  
Vol 62 (s9) ◽  
pp. 41-45 ◽  
Author(s):  
F. Šeršeň ◽  
M. Lácová
Keyword(s):  
Antioxidant Activity ◽  
Acetic Acid ◽  
Superoxide Anion ◽  
The Other ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Coumarin Derivatives ◽  
Antioxidant Effectiveness ◽  
Derivatives Of ◽  
Superoxide Anion Radicals

AbstractNineteen derivatives of coumarin were tested on the scavenging of 2,2-diphenyl-1-picrylhydrazyl, hydroxyl and superoxide anion radicals. It was found that antioxidant activity exhibits only such coumarins that contain hydroxyl groups. The derivatives without hydroxyl group showed very low antioxidant effectiveness or they were ineffective. On the other hand, the greatest antioxidant effectiveness was exhibited by coumarin derivatives that contained hydroxyl groups in 6 or 8 position, whereas the effectiveness of derivatives with one hydroxyl group in 4, 5 or 7 position was very low. Based on scavenging of the above-mentioned radicals, it was found that the most effective scavengers were 7,8-dihydroxy-4-methylcoumarin (i.e. compound that contains two hydroxyl groups in 7 and 8 positions), (7,8-dihydroxy-2-oxo-2H-chromen-4-yl)acetic acid (this compound contains in addition to two hydroxyl groups in 7 and 8 positions also one hydroxyl group in the acidic residue), esculetin (6,7-dihydroxycoumarin) and 6,7-dihydroxy-4-methylcoumarin.

Synthesis of N-(3-Fluoro-2-phosphonomethoxypropyl) (FPMP) Derivatives of Heterocyclic Bases

1993 ◽  
Vol 58 (7) ◽  
pp. 1645-1667 ◽  
Author(s):  
Jindřich Jindřich ◽  
Antonín Holý ◽  
Hana Dvořáková
Keyword(s):  
Heterocyclic Ring ◽  
Hydroxyl Group ◽  
Subsequent Removal ◽  
Heterocyclic Base ◽  
Primary Hydroxyl ◽  
Pyrimidine Bases ◽  
Ether Treatment ◽  
Heterocyclic Bases ◽  
Derivatives Of ◽  
Chiral Synthon

A new group of compounds has been prepared: N-(3-fluoro-2-phosphonomethoxypropyl) (FPMP) derivatives of purine and pyrimidine bases which exhibit a significant selective activity against a broad spectrum of retroviruses. Racemic N-(3-fluoro-2-phosphonomethoxypropyl) derivatives of adenin (V), guanine (IX), cytosine (XIII), 2,6-diaminopurine (XXI), 3-deazaadenin e(XVII), xanthine (X) and hypoxanthin (VI) were prepared from the corresponding N-(3-fluoro-2-hydroxypropyl) derivatives after protection of amino group at the heterocyclic ring by selective benzoylation, reaction with diisopropyl p-toluenesulfonyloxymethylphosphonate (II), and subsequent removal of the protecting groups. Chiral FPMP derivatives were prepared by reaction of heterocyclic base with the corresponding chiral synthon (XXX, XXXVII) followed by deprotection. The required chiral synthons were obtained from enantiomeric 3-fluoro-1,2-propanediols by two methods. In the first, the primary hydroxyl group was tritylated, the obtained derivative was reacted with compound II, the trityl group was removed and the product was mesylated to give synthon XXXVII. The second pathway consisted in selective tosylation of the primary hydroxyl group and conversion of the secondary hydroxyl into the acetoxymethyl ether via the methoxymethyl ether; treatment of the acetoxy compound with bromotrimethylsilane and triisopropyl phosphite afforded the desired synthon XXX.

t-Butyldimethylsilyl ethers of sucrose

1977 ◽  
Vol 30 (3) ◽  
pp. 639 ◽  
Author(s):  
F Franke ◽  
RD Guthrie
Keyword(s):  
Good Yield ◽  
Quantitative Yield ◽  
Hydroxyl Groups ◽  
Carbohydrate Chemistry ◽  
Blocking Group ◽  
Primary Hydroxyl ◽  
Derivatives Of

The usefulness of the t-butyldimethylsilyl group as a blocking group in carbohydrate chemistry has been demonstrated and its selectivity towards primary hydroxyl groups, in the absence of imidazole, shown by preparation of derivatives of methyl α-D-glucopyranoside and sucrose. Methyl α-D-gluco-pyranoside was converted into methyl 6-O-t- butyldimethylsilyl-a-D-glucopyranoside in almost quantitative yield, and sucrose to 6,1?,6?-tri-O-t-butyldimethylsilylsucrose in good yield. In the presence of excess sucrose, a mixture of 6?-O-t- butyldimethylsilyl-, 6,6?-di-O-t-butyldimethylsilyl- and 6,1?,6?-tri-O- t-butyldimethylsilyl-sucroses was formed.

scholarly journals New bio-amphiphilic structures of sucrose via amides linkages

2019 ◽  
Vol 10 (4) ◽  
pp. 3143-3154
Author(s):  
Salih Mahdi Salman
Keyword(s):  
Chemical Structure ◽  
13C Nmr Spectroscopy ◽  
Alkyl Halides ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Staudinger Reaction ◽  
Target Structure ◽  
Leaving Group ◽  
Derivatives Of ◽  
Resolution Mass

A series of four new derivatives of sucrose have been synthesized using the straightforward methodology in order to give a mono substituted analogs of sucrose at C-6’ of fructose moiety. The synthesis was started from the reaction of sucrose with tert-butylchlorodiphenylsilane, which is able to react with an only less steric hindrance hydroxyl group at C-6’ due to its bulky structure. The other hydroxyl groups were acetylated by the reaction with acetic anhydride in pyridine. Then free the hydroxyl group at C-6’ again by the treatment with t-butylammonium fluoride in THF. The later was activated by conversion to a good leaving group via tosylation, followed by functionalized via azidation to give the precursor of the target series hepta-O-acetyl-6’-azido- sucrose. The precursor was coupled with four alkyl halides (C12, C8-4, C14, C10-8) via Staudinger reaction to produced the target structure after deacetylating. The purity and chemical structure of the synthesized compound was confirmed by CHN elemental analysis, high-resolution mass and 1H, 13C NMR spectroscopy. 

scholarly journals XIX. Polyhydroxylic Acceptors for the . ? -Glucosidase of Staohybotrys Atra

1966 ◽  
Vol 19 (6) ◽  
pp. 1153 ◽  
Author(s):  
MAJ ermyn
Keyword(s):  
Hydroxyl Group ◽  
Transfer Product ◽  
Group Transfer ◽  
Secondary Hydroxyl ◽  
Primary Hydroxyl ◽  
Order Of Magnitude

Transfer to polyols appears to take place principally to the terminal primary hydroxyl group. Transfer to the penultimate secondary hydroxyl group in any amount was only demonstrated for the pentitols, adonitol, and L-arabitol. Where the concentrations of the acceptor and the initial transfer product are of the same order of magnitude, there is measurable transfer to the initial transfer product to give molecules containing two glucosyl residues. Where all hydroxyls are secondary, as in myoinositol, no one transfer product predominates.

Glucuronidierung von Hydroxy-testosteron- und Hydroxy-androstendion-Verbindungen durch die mikrosomale UDP-Glucuronyl-Transferase der Rattenleber / Glucuronidation of Hydroxy-compounds of Testosterone and Androstenedione by the Microsomal UDP Glucuronyl Transferase of Rat Liver

1972 ◽  
Vol 27 (1) ◽  
pp. 49-52
Author(s):  
Herbert Schriefers ◽  
Rüdiger Ghraf ◽  
Birgit Lehnen
Keyword(s):  
High Specificity ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Testosterone Metabolism ◽  
Glucuronyl Transferase ◽  
Hydroxy Compounds ◽  
Derivatives Of ◽  
Special Case ◽  
Free Steroid ◽  
Very High

The microsomal UDP glucuronyl transferase exhibits activities against hydroxy derivatives of androstenedione (hydroxyl groups in the positions 2β, 6β or 16α) between 5% and 27% of the extent shown against testosterone. 2β-, 6β· and 16α-hydroxyl groups are much less efficient in accepting the glucuronic acid than the 17β-hydroxyl group.However, the acceptor function of the 17β-hydroxyl group is restricted by other hydroxy substituents in the testosterone molecule to an increasing extent represented by the following sequence: 2α, 6β, 6α, 16α, and 7α. A special case is represented by 2β-hydroxy-testosterone. The transferase displays a higher activity against this compound than against testosterone.Apparently the transferase approaches the steroid molecule from the α-side (with the β-side there is also contact at the C-6 atom) requires the 17β-hydroxyl group and the 3-oxo-4-ene system to display full activity.Thus the very high specificity of the transferase for testosterone explains the selective action of this enzyme on testosterone metabolism in the liver. This action is expressed by the fact, that in liver perfusates the percentage of testosterone in the glucuronide fraction is twice as large as the percentage of testosterone in the free steroid fraction.

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