Acetic acid structure

Therapeutic Function Antiinflammatory Chemical Name 3-Chloro-4-(2-propenyloxy)benzene-acetlc acid Common Name [4-(allyloxy)-3-chlorophenyl] acetic acid Structural Formula Cl... 

Therapeutic Function Antiinflammatory Chamical Name 6-Chloro-a-methylcarbazole-2-acetic acid Structural Formula ci... 

Lumiracoxib, which has been approved in the UK but not by the FDA, has a phenyl acetic acid structure resembling diclofenac rather than the other coxibs... 

P. Simova. Izvest. Bulgar. Akad. Nauk Otdel. Fiz.-Mat. i Tekh, Naidiy Ser. Fiz. 2, 107-46 (1951). IR, Raman association of formic, acetic acids, structure of3-IOOm-... 

Hardwoods also contain minor amounts (2-5%) of a glucomannan, which contains one to two mannose units for every glucose. In general, hardwood hemicelluloses are characterized by high concentrations of xylose and acetic acid structural units, whereas softwood hemicelluloses are relatively rich in mannose. 

It is a naphthalene acetic acid structural analogue available commercially as the acid and its sodium salt and is sold OTC. The drug is fairly comparable to aspirin both in the management and control of disease symptoms. Nevertheless, it has relatively lesser frequency and severity of nervous system together with milder GI-effects. 

Therapeutic Function Antiinflammatory Chemical Name 6-Chloro-0 -methylcarbazole-2-acetic acid Structural Formula CL... 

The parent diphosphinines (Table 6.22) are unknown, and comparatively few derivatives have up to now been characterised. Worthy of note are the 1,4 diphosphoniacyclohexadienes. These di-ylid compounds can be made by reacting ethynyldiphenylphosphines with HBr in acetic acid. Structure analyses of several compounds of this type have shown they are based on flat six-membered rings with rather short C=C distances, thus indicating formula (6.893) in which little or no electron delocalisation occurs around the ring [72,73]. 

The preparation and spectroscopic properties (infrared, ultraviolet, NMR) of iV-alkoxycarbonyl-N -(2-thiazolyl)thioureas (268) have been studied by the Nagano group (78, 264). These compounds react with bromine in acetic acid or chloroform to give 2--alkoxycarbonylimino-thiazolo[3,2-h]thiadiazolines (Scheme 162), whose structures were established by mass spectroscopy, infrared, NMR, and reactivity patterns (481). 

The greater positive character hence the increased acidity of the O—H proton of 2 2 2 tnfluoroethanol can be seen m the electrostatic potential maps displayed m Figure 1 8 Structural effects such as this that are transmitted through bonds are called indue tive effects A substituent induces a polarization m the bonds between it and some remote site A similar inductive effect is evident when comparing acetic acid and its trifluoro derivative Trifluoroacetic acid is more than 4 units stronger than acetic acid... 

Solvolysis of 1 2 dimethylpropyl p toluenesulfonate in acetic acid (75°C) yields five differ ent products three are alkenes and two are substitution products Suggest reasonable structures for these five products... 

Reaction of benzamhde (C6H5NHCC6H5) with chlorine in acetic acid yields a mixture of two monochloro denvatives formed by electrophilic aromatic substitution Suggest reasonable structures for these two isomers... 

Acrolein (H2C=CHCH=0) reacts with sodium azide (NaNj) in aqueous acetic acid to form a compound C3H5N3O in 71% yield Propanal (CH3CH2CH=0) when subjected to the same reaction conditions is recovered unchanged Suggest a structure for the product formed from acrolein and offer an explanation for the difference in reactivity between acrolein and propanal... 

To understand the greater acidity of carboxylic acids compared with water and alcohols compare the structural changes that accompany the ionization of a representa tive alcohol (ethanol) and a representative carboxylic acid (acetic acid)... 

Figure 20 1 shows the structures of various derivatives of acetic acid (acetyl chlo ride acetic anhydride ethyl thioacetate ethyl acetate and acetamide) arranged m order... 

Treatment of 2 4 6 tn tert butylphenol with bromine in cold acetic acid gives the compound CigH29BrO in quantitative yield The infrared spectrum of this compound contains absorptions at 1630 and 1655 cm Its H NMR spectrum shows only three peaks (all singlets) at 8 1 2 13 and 6 9 in the ratio 9 18 2 What is a reasonable structure for the compound" ... 

Chemists and biochemists And it convenient to divide the principal organic substances present m cells into four mam groups carbohydrates proteins nucleic acids and lipids Structural differences separate carbo hydrates from proteins and both of these are structurally distinct from nucleic acids Lipids on the other hand are characterized by a physical property their solubility m nonpolar solvents rather than by their structure In this chapter we have examined lipid molecules that share a common biosynthetic origin m that all their carbons are derived from acetic acid (acetate) The form m which acetate occurs m many of these processes is a thioester called acetyl coenzyme A... 

Again, as with pyridopyrimidines, the main reaction is oxidation of di- or poly-hydro derivatives to fully aromatic structures, often merely by air or oxygen. In some cases the reagent of choice is mercury(II) oxide, whilst other reagents used include sulfur, bromine, chloranil, chromium trioxide-acetic acid, hydrogen peroxide, and potassium ferricyanide, which also caused oxidative removal of a benzyl group in the transformation (306) (307)... 

Nitration of a series of methyl-1,2-benzisoxazoles was studied by Tahkar and Bhawal using fuming nitric acid and sulfuric acid in acetic acid at 100 °C. 3-Methyl-1,2-benzisoxazole gave a mixture of 5-nitro- and 5,7-dinitro-3-methyl-l,2-benzisoxazole, with the 5-nitro isomer predominant. The product obtained from 3,5-dimethyl-1,2-benzisoxazole was the 4-nitro derivative and not the 7-nitro compound as proposed by Lindemann (26LA(449)63). The synthesis of the 7-nitro compound by an alternative method was used as structural proof. Two products were obtained from 3,6-dimethyl-l,2-benzisoxazole and these were the 5-nitro and 5,7-dinitro derivatives. 3,7-Dimethyl-l,2-benzisoxazole was converted into the 5-nitro derivative (Scheme 25) (77lJC(B)l06l). 

Phenyl-l,2-benzisoxazole has been reported to give a disulfonic acid of unknown structure on treatment with 40% oleum (67AHC(8)277). The chlorosulfonation of 1,2-benzisoxazole-3-acetic acid has been reported to give a mixture of the two products shown in Scheme 26. 

Another interesting reaction of the pyrylium salt (396) has been reported (73TL2195). With nitrous acid in alcohol, (396) gave an intermediate (402) which on heating in acetic acid gave the diacylisoxazole (403). The structure of (402) was determined by X-ray crystallography. These ring interconversions are shown in Scheme 96. 

A wide variety of /3-lactams are available by these routes because of the range of substituents possible in either the ketene or its equivalent substituted acetic acid derivative. Considerable diversity in imine structure is also possible. In addition to simple Schiff bases, imino esters and thioethers, amidines, cyclic imines and conjugated imines such as cinnamy-lidineaniline have found wide application in the synthesis of functionalized /3-lactams. A-Acylhydrazones can be used, but phenylhydrazones and O-alkyloximes do not give /3-lactams. These /3-lactam forming reactions give both cis and /raMS-azetidin-2-ones some control over stereochemistry can, however, be exercised by choice of reactants and conditions. 

Camphor was originally obtained from the camphor tree Lauras eamphora in which it appeared in the optically active dextro-rotary form. Since about 1920 the racemic ( ) mixture derived from oil of turpentine has been more generally used. By fractional distillation of oil of turpentine the product pinene is obtained. By treating this with hydrochloric acid, pinene hydrochloride (also known as bomyl chloride) may be produced. This is then boiled with acetic acid to hydrolyse the material to the racemic bomeol, which on oxidation yields camphor. Camphor is a white crystalline solid (m.p. 175°C) with the structure shown in Figure 22.3. 

Let us now return to the question of solvolysis and how it relates to the stracture under stable-ion conditions. To relate the structural data to solvolysis conditions, the primary issues that must be considered are the extent of solvent participation in the transition state and the nature of solvation of the cationic intermediate. The extent of solvent participation has been probed by comparison of solvolysis characteristics in trifluoroacetic acid with the solvolysis in acetic acid. The exo endo reactivity ratio in trifluoroacetic acid is 1120 1, compared to 280 1 in acetic acid. Whereas the endo isomer shows solvent sensitivity typical of normal secondary tosylates, the exx> isomer reveals a reduced sensitivity. This indicates that the transition state for solvolysis of the exo isomer possesses a greater degree of charge dispersal, which would be consistent with a bridged structure. This fact, along with the rate enhancement of the exo isomer, indicates that the c participation commences prior to the transition state being attained, so that it can be concluded that bridging is a characteristic of the solvolysis intermediate, as well as of the stable-ion structure. ... 

This interpretation is supported by results on the acetolysis of the bicyclic tosylates 9 and 10. With 9, after three months in acetic acid at 150°C, 90% of the starting material was recovered. This means that both ionization to a cyclopropyl cation and a concerted ring opening must be extremely slow. The preferred disrotatory ring-opening process would lead to an impossibly strained structure, the /ran -cyclohexenyl cation. In contrast, the stereoisomer 10 reacts at least 2x10 more rapidly because it can proceed to a stable cis-cyclohexenyl cation ... 

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