Acidity hydrolytic

Acylaminothiazoles easily regenerate their 2-aminothiazole counterparts under acidic hydrolytic conditions (120). 

The platelet hist UIline release assay demonstrated that cotton mill dust extract, cotton bract extract, cotton leaf extract, dialyzed CMD extract, polyphenols, compound 48/80, rutin, trimethylamine HCl, quercetin, catechin, tannic acid, ellagic acid and sodium metasilicate all release histamine directly (48). Thus not only do tannin compounds induce histamine release, but they may also form higher molecular weight polymers and contain components that survive acid hydrolytic conditions (48). Tannins are widely distributed in the plant kingdom. 

Acidic hydrolytic products of pyoverdins, (lS)-5-amino-8,9-dihydroxy-(8) and 5,8,9-trihydroxy-2,3-dihydro-l//-pyrimido[l, 2-a]quinolines-3-carboxylic acids were characterized by 13C NMR investigations in DMSO-d6, DMF-d7, and in 1 N DC1 solutions [91ZN(C)993],... 

Market milk and some products manufactured from milk sometimes possess a flavor described as rancid . This term, as used in the dairy industry, denotes implicitly the flavor due to the accumulation of the proper concentrations and types of free fatty acids hydrolytically cleaved from milk fat under the catalytic influence of the lipases normally present in milk. 

Figure 6.1 Common structures associated with ellagitannins include (A) free ellagic acid (hydrolytic product), (B) castalagin (oak wood), (C) Urolithin A (fecal metabolite), and (D) dimeric Sanguiin H-6 (Rubus species).

It is not requisite that the anion eliminated in the step 19 to 20 be a hydroxyl ion, because acid hydrolysis of 5-amino-5-deoxy-l,2-0-isopropylidene - 3 - O - (methylsulfonyl )-a- D -xylofuranose likewise yields 3-pyridinol (21). On subjection to acid hydrolytic conditions which remove the 2V-acetyl group, such N-acetyl derivatives as 5-acetamido-5-deoxy-a-D-xylopyranose (see p. 167) are immediately transformed, through 17, into 3-pyridinol (21). Furthermore, acid hydrolysis of methyl 5-acetamido-5-deoxy-2,3,4-tri-0-methyl-a-D-... 

The partial hydrolysis of the triacylglycerol to mono and diacylglycerol is called Hydrolytic rancidity. The hydrolysis is hastened by the presence of moisture, warmth and lipases present in fats or air. In fats like butter which contains a high percentage of volatile fatty acids, hydrolytic rancidity produces disagreeable odour and taste due to the liberation of the volatile butyric acid. Butter becomes rancid more easily in summer. 

Dichlorocarbene or dibromocarbene adducts of enol esters rearrange under basic or acidic hydrolytic conditions to give homologous a-bromo-a, -enones, e.g. 3 rearranged to 4. ° ... 

Total acidity (hydrolytic acidity or titratable acidity) is present in soil in the pH range of 5.5 to 7.0, as hydroxy Al-polymers among acidic soil components. The method is based on the determination of hydrogen (H+) and aluminium (AF ) ions, retained by the adsorptive complex which goes in the solution via exchange, when the soil is treated with a buffered salt solution which undergoes an alkaline hydrolysis. Aluminium also takes part in the formation of hydrolytic acidity. 

At pH < 2, the Si-O bonds are subjected to acidic hydrolytic cleavage, causing the loss of the bonded phase. 

Figure 3.13. Diagram illustrating Agilent s StableBond chemistry with two steric-hindrance diisopropyl groups in the bonding reagent to protect the Si-0 bond from acid hydrolytic cleavage. Diagram courtesy of Agilent Technologies.

Uracil was first isolated from herring sperm in 1900 and it originates from ribonucleic acids hydrolytic breakdown gives initially the nucleotide which is further cleaved to uridine (1- -D-ribofuranosidouracil) and finally to uracil. Thymine was originally isolated in 1893 from hydrol-yzates of bovine thymus or spleen. It is one of the four bases in deoxyribonucleic acids which on hydrolysis give thymine via thymidine [3-(2 -deoxy-D-ribofuranosido)-thymine]. 

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