Carboxylic Acids 1 Structure

Figure 1. Palytoxin carboxylic acid. (Structure kindly provided by Professor Yoshito Kishi.)...

Spherical vaterite crystals were obtained with 4-mercaptobenzoic acid protected gold nanoparticles as the nucleation template by the carbonate diffusion method [51]. The crystallization of calcium carbonate in the absence of the 4-MBA capped gold nanoparticles resulted in calcite crystals. This indicates that the polymorphs of CaCOj were controlled by the acid-terminated gold nanoparticles. This result indicates that the rigid carboxylic acid structures can play a role in initiating the nucleation of vaterite as in the case of the G4.5 PAMAM dendrimer described above. 

Hydroxyquinoline 7-carboxylic acid (structure shown in Fig. 2) derivatives have been shown to be useful for producing integrase-inhibiting medica-... 

The same technique was also applied to the synthesis of a 10 member Ugi 4CC-derived solution library, where the fluorous tag was embedded into the carboxylic acid structure. The synthesis of the tag and the library synthetic scheme is shown in Figure 7.22. The tag was derived from a bromosilyl perfluorinated compound (C10F21CH2CH2, rather than C6Fi3CFI2CF[2, as for the isoxazolines) reacted with an orthothiobenzoate [164] and further elaborated with trivial chemistry. The library was produced using classical Ugi 4CC conditions and the tag detachment was obtained via treatment with... 

Fig. 8-8. Formation of furan carboxylic acid structures from o-quinone structures by a benzilic acid rearrangement (Hardell and Lindgren, 1975).

Table 20.3 j Acidity of Some Carboxylic Acids Structure K ... 

In an excellent work by Reuter et al. (1983), serious shortcomings in the interpretation of previous oxidation data were demonstrated. They established that mild oxidation of stream humic substances produced large quantities of oxalic acid indicating stream humic substances to be predominantly aliphatic in nature, whereas strong or severe oxidation produced structures stabilized by a 4n -I- 2 overlapping 7r-electron system, attributed mainly to a series of benzene carboxylic acids. Structural interpretation based on the products of severe oxidation would lead one to falsely conclude a greater degree of aromaticity in stream humic substances than actually exists in the unoxidized material. 

The pJ a values of phosphine oxides have been measured. Their deviation from Hammett base behaviour, their Ho dependencies, and their sites of protonation have been studied. The acidifying effects of phosphoryl, phosphinyl, and thiophosphinyl groups have been studied. Ionization constants have been used to examine substituent effects in alkanephosphonic acids and phosphinyl-carboxylic acids, structural correlations in various phosphorus acids, and solvent effects on the properties of thiophosphorus acids. The linear free-energy relationships, which are based mainly on p a data, have been analysed and reviewed. ... 

C4H602)T (C4H70f Cyclopropane carboxylic acid Structures of decomposing ions assumed to be 13/170 g. n, q 425... 

Structure The structures of derivatives of carboxylic acids are derived from the parent carboxylic acid structure. The four... 

The lipophilic carboxylic acid structure of this compound prompted development of further follow-on compounds designed for oral administration. Initial structure-activity relationship analyses led the researchers to the design of an indole-containing lead compound 20 [15]. 

Wu et al., reported syntheses of a series of novel azo polyelectrolytes, starting with a reactive precursor, poly(acryloyl chloride). The precursor polymer was functionalized by the Schotten-Baumann reaction with several aromatic azo compounds containing hydroxyl end groups. The degrees of functionalization were controlled by selecting suitable feed ratios between the azo reactants and poly(acryloyl chloride) The unreacted acyl chloride groups were hydrolyzed to obtain ionizable carboxylic acid structures. 

Fig. 9.2. X-ray crystal structures of (A) l,6-methanodeca-l,3,5,7,9-pentaene and (B) 1,6-methanodeca-l,3,5,7,9-pentaene-2-carboxylic acid. [Structures are reproduced from Refs. 27 and 28.]...

LINEHAN D.J. 1978. Ihe uptake of plants of polymaleic acid a poly-carboxylic acid structurally related to those of soil. Plant and Soil, 50, 625-632. 

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