Sugars acid anhydrides

Inositols, ie, hexaliydrobenzenehexols, are sugars that have received increasing study and are useful in the treatment of a wide variety of human disorders, including vascular disease, cancer, cirrhosis of the Hver, frostbite, and muscular dystrophy (269). Myoinositol esters prepared by reaction with lower fatty acid anhydrides are useful as Hver medicines and nonionic surfactants the aluminum and ammonium salts of inositol hexasulfate are useful anticancer agents (270). Tetraarjloxybenzoquinones are intermediates in the preparation of dioxazine dyes (266,271). The synthesis of hexakis(aryloxy)benzenes has also beenpubUshed (272). 

A primed numeral locates the position of the phosphate on the sugars of mononucleotides (eg, 3 -GMP, 5 -dCMP). Additional phosphoryi groups linked to the first by acid anhydride bonds form nucleoside diphosphates and triphosphates. 

The name, maleic anhydride, came about in the same fashion. as any number of compounds early in the petrochemical Business Many organic acids and their derivatives were given common names based on some early observations, their special source in nature, or on some special feature of their structure. MA was first isolated in the 1850—75 era by dehydration of malic acid, a sugar acid found in apple juice. The Latin word for apple is malum. Hence, malum, malic, maleic. The suffix, anhydride, which follows each alias of MA, has a simple definition a compound derived by the loss of a molecule of water from two carboxyl groups (-COOH). 

Peracylation can be achieved by treatment of the amino sugar with the appropriate acid anhydride or chloride in pyridine at room temperature87 or with the acid anhydride and the sodium salt of the acid at a higher temperature88 the resulting product is usually a mixture of the a and 0 anomers... 

When sugars are treated with appropriate acid anhydride or acid chloride under proper conditions, the hydroxyl groups get esterified and form sugar esters. 

Pyridine is used in catalytic amounts and acylpyridinium salts are assumed to be the reactive acylating agents. The method can be applied to the synthesis of both symmetrical and unsymmetrical acid anhydrides. " These can also be obtained in many cases directly from the acid halide and the sodium carbox-ylate without using a solvent or a catalyst. Tiiis approach has been described for a number of mixed acid anhydrides. Thus acetic palmitic anhydride (70%), butyric myristic anhydride (81%) and caproic lauric anhydride (85%) were prepared by heating the components for 2 h at 90 °C. 75 These anhydrides were successfully employed for the N-acylation of amino sugars. 7 ... 

Glycosylation. A glycoside with one free hydroxyl group and another protected sugar (except the OH at the anomeric center) condense on treatment with the aid of an acid anhydride and Me3SiC104, which is prepared in situ from MeaSiCl and AgCl04. 

C2-homologizati on of sugars with, 264-265 Acetamide, JV-bromo- (AcNHBr, NBA) bromohydrination with, 275-276, 287 Acetaminophen (= paracetamol), 301 Acetate, piperidinium cat. for aldol add., 82 —, sodium a-epimerization of ketones, 277 opening of oxiranes, 282 Acetic acid, anhydride (AcfO) protection with. See Protection Pummerer rearr. with, 51, 265 —, esters (See also Protection of hydroxy groups) C-H acidity, 10 1-methylethenyi ester pr., 174 transenolization, 58 —, bromo-, esters pr., 179 a2-synthon, 19, 65, 309 d2-synthon, 19, 301 —, chloro-, esters pr., 179 hydantoins from, 308 —, cyano-, esters pr., 177 pyrrolines from, 298 —, (dialkoxyphosphinyl)-, esters pr 188 Wittig-Horner olefinations, 267, 282 —, diazo-, ethyl ester pr, 176, 178 cyclopropanes from, 74—75 —, dichloro- deblocking of pixyl ethers, 342 —, hydroxy-, esters pr., 176 —, hydroxyphenyl-, (S)- (l-mandelic acid) ... 

Guanosine and 2 -deoxyguanosine can be acylated in high yield on the sugar unit but not the heterocycle by use of an acid anhydride and DMAP in acetonitrile/triethyl2unine. 2 -Deoxyribonucleosides have been converted efficiently into their 5 0-aroyl derivatives by treatment in pyridine with a dilute solution of the aroyl chloride in pyridine,whilst in the rlbonucleoside series peracylated systems can be selectively unblocked at 0-2 and 0-3 in yields adsove 80% by the use of sodium methoxide in Additionally, peraroylated ribo-... 

A series of castor oil-based ester derivatives were prepared by the esterification of castor oil with acid anhydrides such as phthalic, maleic and succinic anhydrides. The effect of different concentrations of castor oil and its esters on the growth activities of the sugar beet pathogens Rhizoctonia solani and Sclerotium rolfsii was studied by determining the percentage... 

There has been some interest in the use of trifluoroacetylated oximes as volatile derivatives for GC analysis of sugars, as analysis can be performed at relatively low temperatures and the sensitive electron capture detector can be used. However, these derivatives are unstable in the presence of moisture, and it is therefore difficult to remove the derivatization reagent (trifluoroacetic acid anhydride) compounds other than sugars may thus be converted to halogenated derivatives, resulting in increased... 

The net effect of this questionable attitude thrust upon FDA was that sucrose esters went into commercial production in Japan rather than in the land of their discovery. In Japan they go into cake mixes as emulsifying agents, and so far they have hurt no one. The process of digestion splits the sucrose ester into fatty acid and invert sugar, compounds that are normally present in the body. More recently I have seen reports that the French are using sucrose esters in animal feeds. The results of experiments synthesizing sucrose esters from acid anhydrides, to be reported later in this symposium, are, naturally, of great interest to me. 

The reaction is freely reversible and the enzyme catalyzing it has been called DPN pyrophos-phorylase. This transfer of one 5 -nucleotide to another produces a pyrophosphate bond between them. The reaction is the prototype of a large number of such nucleotidyl transfers to other phosphate compounds. These include transfers to various sugar phosphates to form the nucleoside diphosphate sugar coenzymes, to choline phosphate to form C3fiidine diphosphate choline, and to phosphatidic acid to form cytidine diphosphate diglyceride. This nucleotidyl transfer is the protot)q)e also for transfers of nucleotides to produce mixed acid anhydrides with fatty acids, amino acids, and sulfates. In each instance inorganic pyrophosphate is produced this is also true of the nucleotidyl transfers which produce RNA and DNA. 

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