Investigation of acylation of β-cyclodextrin and its silyl derivative with benzoyl and acetylsalicyloyl chlorides

Abstract Methods for the determination and confirmation of N-nitrosodiethanolamine (NDELA) in cosmetic products were developed. The NDELA fraction was isolated from a cosmetic product by a series of solvent extractions which were designed to concentrate the NDELA and remove ingredients deleterious to the analytical system. The isolated fraction was then analyzed for NDELA using a high pressure liquid chromatograph (HPLC) interfaced with a thermal energy analyzer (TEA). The compound was measured by comparison of detector response with those of known standards. NDELA was verified by gas chromatography-mass spectrometry of the silyl derivative after preliminary cleanup of the sample by gradient elution HPLC on a Partisil 10 PAC column. The limit of detection of NDELA by TEA is 2-3 ng, which corresponds to 20-30 ppb in the cosmetic product. Analysis of an emulsion cream and a hair grooming gel spiked at 3 and 4 ng concentration levels, respectively, yielded recoveries ranging from 71 to 103% (average 88%).

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Dramatic slowing down of the conformational equilibrium in the silyl derivative of glucose in the vicinity of the glass transition temperature

Soft Matter ◽

10.1039/c9sm01259a ◽

2019 ◽

Vol 15 (37) ◽

pp. 7429-7437 ◽

Cited By ~ 1

Author(s):

K. Wolnica ◽

M. Dulski ◽

E. Kamińska ◽

M. Tarnacka ◽

R. Wrzalik ◽

...

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Conformational Equilibrium ◽

Silyl Derivative ◽

Slowing Down

This paper reports significantly slowed down of the rotations of silyl moieties along with the deformation in the saccharide ring in 1,2,3,4,6-penta-O-(trimethylsilyl)-d-glucopyranose (S-GLU) in the vicinity of the glass transition temperature.

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Liquid Silyl Derivative of beta-Cyclodextrin

Macroheterocycles ◽

10.6060/mhc170520g ◽

2017 ◽

Vol 10 (2) ◽

pp. 233-237

Author(s):

Askar K. Gatiatulin ◽

Marat A. Ziganshin ◽

Galina I. Kurochkina ◽

Artem V. Popkov ◽

Mikhail K. Grachev ◽

...

Keyword(s):

Silyl Derivative ◽

Beta Cyclodextrin

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Gas-Liquid Chromatographic Determination of Adipate Content of Acetylated Di-starch Adipate

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/65.2.238 ◽

1982 ◽

Vol 65 (2) ◽

pp. 238-240

Author(s):

Gordon A Mitchell ◽

Michel J Vanderbist ◽

Florent F Meert

Keyword(s):

Ethyl Acetate ◽

Adipic Acid ◽

Silicone Oil ◽

Internal Standard ◽

Active Phase ◽

Chromatographic Determination ◽

Silyl Derivative ◽

Alkaline Conditions ◽

Liquid Chromatographic

Abstract A gas-liquid chromatographic method is described for rapid, quantitative determination of adipate content of acetylated di-starch adipate. The adipate group is very labile and, under mild alkaline conditions at ambient temperature, is easily hydrolyzed from the starch. Free adipic acid is formed by acidification of the solution with HC1, and then extracted with ethyl acetate. Ethyl acetate is removed under vacuum distillation, and a silyl derivative of the adipic acid is formed. Glutaric acid internal standard is introduced into the original starch sample before hydrolysis. An aliquot of the silylated solution is injected into a gas chromatograph fitted with a column having silicone oil as the active phase. A flame ionization detector is also incorporated. Results correlate well with the amount of adipylating reagent used. No adipic acid is detectable when a hydrolyzed, extracted sample of acetylated di-starch adipate is subjected to a second extraction. Recovery levels of adipic acid, from starches fortified with 100-500 ppm, are in the range of 97-102.5.%

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2',3'-Dideoxy- and 3'-Azido-2',3'-dideoxynucleosides of 5-Phenyl-2(1H)-pyrimidinone. Preparation of 2',3'-Dideoxypentofuranoses

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19960478 ◽

1996 ◽

Vol 61 (3) ◽

pp. 478-488 ◽

Cited By ~ 6

Author(s):

Marcela Krečmerová ◽

Hubert Hřebabecký ◽

Milena Masojídková ◽

Antonín Holý

Keyword(s):

Acetic Anhydride ◽

Thionyl Chloride ◽

Benzoyl Chloride ◽

Chromium Trioxide ◽

Minor Amount ◽

Subsequent Reduction ◽

Silyl Derivative ◽

Chloro Derivative ◽

Trimethylsilyl Trifluoromethanesulfonate ◽

Keto Derivative

The synthesis of methyl 3-azido-5-benzoyl-2,3-dideoxy-β-D-ribofuranoside (10) from methyl 2-deoxy-D-ribofuranoside (1) and its use for the preparation of 3'-azido-2',3'-dideoxy-β-D-ribofuranosides is described. Reaction of methylglucoside 1 with benzoyl chloride in pyridine afforded 5-O-benzoyl derivative 2, which on oxidation with complex of chromium trioxide, pyridine and acetic anhydride afforded 3-keto derivative 3. This was reduced with sodium borohydride in ethanol to give a mixture of methyl 2-deoxyglycosides of α-D-ribo- (4) and β-D-xylo- (5) configuration. Their mesyl derivatives 6 and 7 were chromatographically separated. Compound 7 reacted with sodium azide in hot dimethylformamide to afford methyl 3-azido-5-O-benzoyl-2,3-dideoxy-β-D-ribofuranoside (10). 5-Phenyl-2(1H)-pyrimidinone was converted into silyl derivative 11 by treatment with hexamethyldisilazane. Reaction of compound 11 with the azido sugar 10, catalyzed by trimethylsilyl trifluoromethanesulfonate, and subsequent methanolysis, furnished a mixture of anomeric 3'-azido-2',3'-dideoxynucleosides 14 and 15. Methyl 5-O-benzoyl-2,3-dideoxy-α-D-ribofuranoside (17) was prepared from methyl-α-glycoside 4 by reaction with thionyl chloride and subsequent reduction of the obtained 3-chloro derivative 16 with tributylstannane. Silyl derivative 11 reacted with 2,3-dideoxy sugar 17 under catalysis with trimethylsilyl triflate to give mainly 1-(5-O-benzoyl-2,3-dideoxy-α-D-glycero-pentofuranosyl)-5-phenyl-2(1H)-pyrimidinone (19) and minor amount of the β-anomer 18. Their methanolysis afforded dideoxynucleosides 20 and 21.

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ChemInform Abstract: Lignans. Part 19. Total Synthesis of (-)-O-Dimethylsugiresinol (VI), Involving Asymmetric (4 + 2) Heterocycloaddition of a Styrene with a Benzylidenepyruvic Ester of an α-O-Silyl Derivative of (D)- Erythronolactone.

ChemInform ◽

10.1002/chin.199750277 ◽

2010 ◽

Vol 28 (50) ◽

pp. no-no

Author(s):

E. BROWN ◽

G. DUJARDIN ◽

M. MAUDET

Keyword(s):

Total Synthesis ◽

Silyl Derivative

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A bulky silyl derivative of tin(II)

Journal of Organometallic Chemistry ◽

10.1016/0022-328x(87)80413-8 ◽

1987 ◽

Vol 325 (1-2) ◽

pp. C11-C13 ◽

Cited By ~ 38

Author(s):

Atta M. Arif ◽

Alan H. Cowley ◽

Tammy M. Elkins

Keyword(s):

Silyl Derivative

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Synthesis of 5-Phenyl-2(1H)-pyrimidinone Nucleosides

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19960458 ◽

1996 ◽

Vol 61 (3) ◽

pp. 458-477 ◽

Cited By ~ 4

Author(s):

Marcela Krečmerová ◽

Hubert Hřebabecký ◽

Milena Masojídková ◽

Antonín Holý

Keyword(s):

Thionyl Chloride ◽

Chloroacetic Acid ◽

Equilibrium Mixture ◽

Side Product ◽

Subsequent Reaction ◽

Silyl Derivative ◽

Tetrabutylammonium Fluoride ◽

Trimethylsilyl Trifluoromethanesulfonate ◽

Methanolic Ammonia ◽

Tin Tetrachloride

Reaction of 2-phenyltrimethinium salt 1 with thiourea and subsequent reaction with chloroacetic acid afforded 5-phenyl-2(1H)-pyrimidinone (3). Its silyl derivative 4 was condensed with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose under catalysis with tin tetrachloride or trimethylsilyl trifluoromethanesulfonate to give protected nucleoside 5 together with 5',O6-cyclo-5-phenyl-1,3-bis- (β-D-ribofuranosyl)-6-hydroxy-5,6-dihydro-2(1H,3H)-pyrimidinone (7). The greatest amounts of 7 were formed with the latter catalyst. Nucleosidation of the silyl derivative 4 with protected methyl 2-deoxy-D-ribofuranoside 8 or 2-deoxy-D-ribofuranosyl chloride 9 afforded 1-(2-deoxy-3,5-di-O-p-toluoyl-β-D-ribofuranosyl)-5-phenyl-2(1H)-pyrimidinone (10) and its α-anomer 11. Reaction of 10 and 11 with methanolic ammonia gave free 2'-deoxynucleosides 12 and 13. Compound 13 was converted into 5'-O-tert-butyldiphenylsilyl-3'-O-mesyl derivative 14 which on heating with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and subsequent cleavage with tetrabutylammonium fluoride afforded 2',3'-dideoxy-2',3'-didehydronucleoside 15. Reaction of the silyl derivative 4 with 1,2-di-O-acetyl-3,5-di-O-benzoylxylofuranose (18), catalyzed with tin tetrachloride, furnished 1-(2-O-acetyl-3,5-di-O-benzoyl-β-D-xylofuranosyl)-2(1H)-pyrimidinone (19) which was deprotected to give the β-D-xylofuranosyl derivative 22. As a side product, the nucleosidation afforded the β-D-xylopyranosyl derivative 23. Deacetylation of compound 19 gave 1-(3,5-di-O-benzoyl-β-D-xylofuranosyl)-5-phenyl-2(1H)-pyrimidinone (24) which on reaction with thionyl chloride afforded 2'-chloro-2'-deoxynucleoside 25 and 2',O6-cyclonucleoside 26. Heating of compound 25 with DBU in dimethylformamide furnished the lyxo-epoxide 27 which on reaction with methanolic ammonia was converted into free 1-(2,3-anhydro-β-D-lyxofuranosyl)-5-phenyl-2(1H)-pyrimidinone (28). Reaction of 1,2-di-O-acetyl-5-O-benzoyl-3-O-methanesulfonyl-D-xylofuranose (30) with silyl derivative 4 gave the nucleoside 31 which by treatment with DBU was converted into an equilibrium mixture of 5'-benzoylated arabinofuranoside 33a and its 2',6-anhydro derivative 33b.

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