Solubility equations

A series of studies has been made by Yalkowsky and co-workers. The so-called general solubility equation was used for estimating the solubility of solid nonelectrolytes [17, 18]. The solubility log S (logarithm of solubility expressed as mol/L) was formulated with log P logarithm of octanol/water partition coefficient), and the melting point (MP) as shown in Eq. (11). This equation generally... [Pg.495]

Yang G, Ran Y and Yalkowsky SH. Prediction of the aqueous solubility comparison of the general solubility equation and the method using an amended solvation energy relationship. J Pharm Sci 2002 91 517-33. [Pg.508]

Sanghvi, T., Jain, N Yang, G., Yalkowsky, S. Estimation of aqueous solubility by the general solubility equation (GSE) the easy way. QSAR Comh. Sci. 2003, 22, 258-262. [Pg.282]

The coefficients of descriptors A, AB and S are not statistically significant, but the terms are left in the equation for comparison with Abraham and Le s [8] water-solubility equation, modified here to conform to the mathematical conventions used in this chapter ... [Pg.237]

The 1,3-dipolar cycloaddition of azidofurazans to acetylenes afforded 1,2,3-triazoles linked with furazan cycle <2000CHE91>. Treatment of 3-azido-2-amino-l,2,5-oxadiazole 194 with ethyl 4-chloroacetoacetate gives access to the functionalized [l,2,3]-triazoles 195, which are good precursors for GSK-3 inhibitors with favorable water solubility (Equation 38) <2003JME3333>. [Pg.352]

A We calculate the solubility of silver cyanate, s, as a molarity. We then use the solubility equation to (1) relate the concentrations of the ions and (2) write the K expression. [Pg.450]

As far as we know, the literature contains no quantitative information on the solubility of carbocation salts and the qualitative information available indicated that such salts are relatively insoluble in the solvents of interest. Our first problem was to predict how changes in the structure of the salt would affect the solubility. Although the ideal solubility equation [Equation (1)] cannot be applied rigorously to ionic solutes, our first step was to examine its utility. [Pg.191]

The ideal solubility equation (Eq. 2) is the simplest form of model that is applicable to solvent based crystallization process design. Even though the equation excludes non-ideal interactions in the liquid phase, it is still a useful tool in certain circumstances. [Pg.52]

In systems where the liquid phase interaction between the solute and solvent is close to ideal, then Eq. 2 can be used successfully on it s own to fit and extrapolate solubility data with respect to temperature. The technique is valuable in an industrial setting, where time pressures are always present. Solubility data points are often available without any additional effort, from initial work on the process chemistiy. The relative volume of solvent that is required to dissolve a solute at the highest process temperature in the ciystallization is often known, together with the low temperature solubility by analysis of the filtrates. If these data points fit reasonably well to the ideal solubility equation then it can be used to extrapolate the data and predict the available crystallization yield and productivity. This quickly identifies if the process will be acceptable for long term manufacture, and if further solvent selection is necessary. [Pg.52]

A primary role of crystallization is to purify the desired product and exclude impurities. Such impurities are frequently related in chemical structure to the desired product, through the mechanisms of competitive reaction and decomposition. Where the impurities are similar in structure it is likely that their interactions with the solvent in the liquid phase will also be similar. In this instance the selectivity of crystallization is mainly attributed to the difference between the respective pure solid phases. The ideal solubility equation can be applied to such systems [5, 8] on a solvent free basis to predict the eutectic composition of the product and its related impurities. The eutectic point is a crystallization boundary and fixes the available yield for a single crystallization step. [Pg.52]

The ideal solubility equation has significant value in chiral systems, where a single enantiomer is desired as the product [20]. The behaviour of chiral compounds is very important in biological systems and in drug development, where it is typical for just one enantiomer of an API to be biologically active. The undesired enantiomer may be inert, or possess more serious toxicity effects, as in the case of Thalidomide. Many enantiomeric systems form three discrete solid phases, depending on the solution concentration. Pure crystals of each enantiomer will form at high concentrations of their respective enantiomer. At... [Pg.52]

Comparing Eq. 4 with the ideal solubility equation, Eq. 2 shows that ... [Pg.60]

Ran, Y., Jain, N., Yalkowsky, S.H. Prediction of aqueous solubility of organic compounds by the general solubility equation (GSEJ./. Chem. Inf. Comput. Sci. 2001, 41, 1208—1217. [Pg.39]

For ionizing substances that are only slightly soluble, the concentrations of the ions multiply to a constant called the solubility product in a saturated solution. For a hypothetical compound CA, where the single cation is denoted by C and the anion by A, the solubility equation is... [Pg.93]

Many binary compounds (those with only 2 elements) contain more than 1 cation or anion. The general binary compound can be written CW, in which the subscripts mean the compound has x cations and y anions. In this case, the solubility equation is... [Pg.93]

Table 9-2 states that for Ag2C03 is 8.5 X 10 l The solubility equation... [Pg.93]

The other term frequently occurring in such equations is the octanol-water partition coefficient, logP. It describes the lipophilicity of the compound. It is related to water solubility by Yalkowski s general solubility equation (GSE) ]33, 34] ... [Pg.32]

Ran, Y. and Yalkowsky, S.H. (2001) Prediction of drug solubility by the general solubility equation (GSE). Journal of Chemical Information and Computer Sciences, 41, 354—357. [Pg.41]

According to Equation (4.5) the ideal solubility of a compound is only dependent upon the heat of fusion, the difference in heat capacity of the solid and supercooled liquid and the melting point of the compound. Since there are no properties of the solvent included in the ideal solubility equation, the solubility of a compound should be the same in all solvents. This equation overlooks all solute-solvent and solvent-solvent interactions. [Pg.77]

A comprehensive review of this field is beyond the scope of this chapter. As for vapour pressure, the aim is to give easy-to-use tools for non-specialists in the field. The general solubility equation, initially introduced by Yalkowski and Valvany [47], then revised by the same team [48], is probably the simplest ... [Pg.588]

As early as 1819, J. L. Gay Lussac proposed to represent the solubility S of potassium chloride in water at a temp. 0 by the formula /S=29-23+0-27380 grms. per 100 grms. of water. Since that time it has been customary to represent solubility curves by empirical formula of the type /S=a+ 0+d02+..., where a, l, c,d,.. . are constants whose numerical values are calculated from the experimental data. Equations of the type S=a- -bO represent straight lines, equations with more terms represent curved lines the solubility equation /S=d+60+c02 represents a portion of a paraboloid curve. The greater the number of terms used in the formula the greater is supposed to be the accuracy of the result. [Pg.540]

Equations similar to those for mutarotation have been derived, expressing the relationship between the solubility behavior of the two forms of lactose and the equilibrium or rate constants (Hudson 1904). The constants derived by both mutarotation and solubility methods are in agreement. The solubility equations have been used to develop procedures for measuring a- and /3-lactose in dry milk (Roetman 1981). [Pg.300]

AQUAFAC Approach The AQUAFAC approach is based on the following solubility equation [48,49] ... [Pg.131]

Am in Equation 3.3 is the Luidization term accounting forthe hypothetical melting of a crystalline solute in the dissolution process takes the same expression for crystalline material used in the regular solubility equation, assuming that heat capacity is the same for both the crystalline and the hypothetical molten solute ... [Pg.25]

The next step in developing the solubility equation by partition theory is the estimation of the activity coefLcient of solute in watersolution. If an aqueous solution is equilibrated with octanol, then it can be shown th i can be related to the octanol-water partition coefLcient by... [Pg.29]

For substances that are liquid af E5 the solubility equation is further reduced to... [Pg.30]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...