Steroid and bile acids amide conjugates with D-glucosamine

2011 ◽  
Vol 76 (1) ◽  
pp. 65-74
Author(s):  
Zdena Nováková ◽  
Jana Tomanová ◽  
Lucie Štěrbová ◽  
Pavel Drašar
Keyword(s):  
Acetic Acid ◽  
Bile Acids ◽  
Acid Chloride ◽  
Acetyl Chloride ◽  
Glucosamine Hydrochloride ◽  
Negative Results ◽  
Step Procedure ◽  
One Step ◽  
New Type

New type of amide conjugates of steroid and bile acids with D-glucosamine 1 and 2 were prepared. Title compounds are prepared via acid chloride or using N-[({[(1E)-1-cyano-2-ethoxy-2-oxoethylidene]amino}oxy)(dimethylamino)methylidene]-N-methylmethanaminium tetrafluoroborate as condensation agent. They were examined for gelation properties with negative results. Per-O-acetylated D-glucosamine hydrochloride was prepared in one step procedure from D-glucosamine hydrochloride by acetylation in a mixture of acetyl chloride and acetic acid.

Hot-Tube Reactions of Dehydroabietic Acid with Ketene-Producing Reagents. Pyrolysis of the Acid Chloride and Symmetrical and Mixed Anhydride Derivatives of Dehydroabietic Acid

1973 ◽  
Vol 51 (19) ◽  
pp. 3236-3241 ◽  
Author(s):  
Ray F. Severson ◽  
Walter H. Schuller
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Acid Chloride ◽  
Acetyl Chloride ◽  
Dehydroabietic Acid ◽  
Mixed Anhydride ◽  
Temperature Range ◽  
Acid Isomerization ◽  
Derivatives Of ◽  
Isopropenyl Acetate

Dehydroabietic acid (1a) was reacted with diketene, acetic acid, acetic anhydride, isopropenyl acetate, acetyl chloride, and acetone on Vycor rod at 450 °C in a hot tube. Dehydroabietic anhydride (1b) and acetyl dehydroabietate (1c) were pyrolyzed at 450 °C and dehydroabietyl chloride (1d) was pyrolyzed over a temperature range of 290–500 °C. The major olefin products resulting from decarboxylation of the various derivatives were 19-norabieta-4,8,11,13-tetraene (2), 19-norabieta-4(18),8,11,13-tetraene (3), 19-norabieta-3,8,11,13-tetraene (4), and cis-1,10a-dimethyl-7-isopropyl-1,2,3,9,10,10a-hexahydrophenanthrene (5). High conversions to these compounds were obtained. In the presence of the ketene-producing reagents the olefins were oxidized to yield substantial amounts of retene (6), compounds 2 and 5 being the most readily dehydrogenated. The acid isomerization of 2, 3, 4, and 5 was studied using p-toluenesulfonic acid in toluene at 110 °C.

Synthesis of Casein-Related Peptides and Phosphopeptides. X. A Modified Method for the Synthesis of Ser(P)-Containing Peptides Through 4-Bromobenzyl Phosphate Protection

1991 ◽  
Vol 44 (3) ◽  
pp. 389 ◽  
Author(s):  
JW Perich ◽  
RB Johns
Keyword(s):  
Acetic Acid ◽  
Formic Acid ◽  
Peptide Synthesis ◽  
Acid Solutions ◽  
Isobutyl Alcohol ◽  
Modified Method ◽  
Step Procedure ◽  
One Step ◽  
Phosphate Protection

The three 4-halobenzyl phosphoramidite reagents di (4-fluorobenzyl) N,N- diisopropylphosphor-amidite, di (4-chlorobenzyl) N,N- diisopropylphosphoramidite and di (4-bromobenzyl) N,N-diethylphosphoramidite were prepared and used for the efficient phosphite-triester phosphorylation of isobutyl alcohol. While all three 4-halobenzyl groups were cleaved at similar rates from the 4-halobenzyl phosphorotriesters by 4 M HCl/dioxan or 50% CF3CO2H/CH2Cl2, the 4-bromobenzyl group had greater stability than either the 4-fluorobenzyl or 4-chlorobenzyl groups in formic acid or 1 M HCl /acetic acid solutions. The protected 4-bromobenzyl derivative, Boc-Ser(PO3BrBzl2)-OH, was prepared by a novel one-step procedure which featured di-4-bromobenzyl N,N- diethylphosphoramidite as phosphitylating agent. This derivative was used for the synthesis of Boc-Glu ( OBzl )-Ser(PO3BrBzl2)- Leu-OBzl by the Boc mode of peptide synthesis with 98% formic acid being used for the cleavage of the Boc group. Palladium-catalysed hydrogenolysis of the protected Ser(PO3BrBzl2) tripeptide in formic acid gave zwitterionic Glu -Ser(P)-Leu in high overall yield.

NON-SUPPRESSIBLE INSULIN-LIKE ACTIVITY AND SULPHATION ACTIVITY IN SERUM EXTRACTS OF NORMAL SUBJECTS, ACROMEGALICS AND PITUITARY DWARFS

1976 ◽  
Vol 81 (1) ◽  
pp. 28-42 ◽  
Author(s):  
U. Schlumpf ◽  
R. Heimann ◽  
J. Zapf ◽  
E. R. Froesch
Keyword(s):  
Molecular Weight ◽  
Growth Hormone ◽  
Acetic Acid ◽  
Large Scale ◽  
Normal Subjects ◽  
Step Procedure ◽  
Chromatographic Procedure ◽  
One Step ◽  
Insulin Like Activity

ABSTRACT Non-suppressible insulin-like activity (NSILA) is a term used for a variety of substances in serum, excluding insulin, which promote glucose uptake of adipose tissue and diaphragm in vitro. NSILA-S is a peptide with a molecular weight of 7000 which is soluble in acid ethanol and which has been purified on a large scale from human serum. This study describes a simple chromatographic one step procedure by which NSILA-S can be extracted and quantitatively measured in individual sera. Using Sephadex G-75 equilibrated with 1 m acetic acid, NSILA-S was detected only in one peak containing small molecular peptides. NSILA-S obtained with this one step chromatographic procedure exerted all the effects of purified NSILA-S including sulphation activity on the rat cartilage. All chromatographic fractions with NSILA-S also had sulphation activity. Both, NSILA-S and sulphation activity were increased in acromegalics and decreased in pituitary dwarfs. It is suggested that one molecule in serum is responsible for both activities which are, at least in part, under the control of growth hormone.

scholarly journals Electrochromic Performance and Capacitor Performance of α-MoO3 Nanorods Fabricated by a One-Step Procedure

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 783
Author(s):  
Ying Duan ◽  
Chen Wang ◽  
Jian Hao ◽  
Yang Jiao ◽  
Yanchao Xu ◽  
...  
Keyword(s):  
Growth Parameters ◽  
Average Diameter ◽  
Fast Response ◽  
Cycle Stability ◽  
Electrochromic Devices ◽  
Step Procedure ◽  
One Step ◽  
Supercapacitor Performance ◽  
First Time ◽  
Prepared Nanorods

In this paper, we propose for the first time the synthesis of α-MoO3 nanorods in a one-step procedure at mild temperatures. By changing the growth parameters, the microstructure and controllable morphology of the resulting products can be customized. The average diameter of the as-prepared nanorods is about 200 nm. The electrochromic and capacitance properties of the synthesized products were studied. The results show that the electrochromic properties of α-MoO3 nanorods at 550 nm have 67% high transmission contrast, good cycle stability and fast response time. The MoO3 nanorods also exhibit a stable supercapacitor performance with 98.5% capacitance retention after 10,000 cycles. Although current density varies sequentially, the nanostructure always exhibits a stable capacitor to maintain 100%. These results indicate the as-prepared MoO3 nanorods may be good candidates for applications in electrochromic devices and supercapacitors.

One-step procedure for the preparation of tertiary .alpha.-ketols from the corresponding ketones

1968 ◽  
Vol 33 (8) ◽  
pp. 3294-3297 ◽  
Author(s):  
J. N. Gardner ◽  
F. E. Carlon ◽  
O. Gnoj
Keyword(s):  
Step Procedure ◽  
One Step

An innovative and efficient method to synthesize meloxicam in one-step procedure with respect to the green chemistry

2018 ◽  
Vol 16 (3) ◽  
pp. 501-509 ◽  
Author(s):  
Pierrick Dufrénoy ◽  
Alina Ghinet ◽  
Marie Hechelski ◽  
Adam Daïch ◽  
Christophe Waterlot
Keyword(s):  
Green Chemistry ◽  
Efficient Method ◽  
Step Procedure ◽  
One Step

scholarly journals An effective GC method for the determination of the fatty acid composition in silkworm pupae oil using a two-step methylation process

2015 ◽  
Vol 80 (1) ◽  
pp. 9-20 ◽  
Author(s):  
Jun Wang ◽  
Weiwei Wu ◽  
Xudong Wang ◽  
Min Wang ◽  
Fuan Wu
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Methyl Esters ◽  
Superior Performance ◽  
Step Procedure ◽  
Silkworm Pupae ◽  
Chromatographic Procedure ◽  
One Step ◽  
Synthesis Yield

In search of an accurate and effective method to determine fatty acid composition in silkworm pupae oils, five methylation methods were evaluated for use in the gas chromatographic (GC) quantitation of fatty acid methyl esters (FAMEs), including one-step esterification catalyzed by an acidic (H2SO4 and BF3) or alkali catalyst (KOH and NaOCH3) and a two-step procedure catalyzed successively by KOH and H2SO4. These methods were comparatively adopted to quantify FAMEs in silkworm pupae oil using GC-MS and GC and then validate their precision, stability and average recovery rates. The results indicated that compared with the other four methyl esterification methods, two-step methylation effectively improves the synthesis yield of FAMEs, conserves agents, and eliminates the usage of potential harmful reagents. The proposed GC method has been validated, shows good accuracy and precision, and has been applied successfully to the quantification of FAMEs in several varieties of silkworm pupae oils. The short analytical run time leads to low costs and a fast chromatographic procedure. In summary, two-step pretreatment had superior performance, providing technical references for the determination and analysis of fatty acids in other oils.

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