ACD/Solubility

Advanced Chemistry Development Inc., Toronto, Canada. ACD/Solubility DB computer program, http //www.acdlabs. com. 

We have studied the performance of several prediction methods to see how well in-house thermodynamic solubility measurements could be predicted. Among the prediction methods we studied were Huuskonen s method [26], ACD/Solubility DB [38], Meylan s method [21] as implemented in QMPRPlus, and the SimulationsPlus solubility prediction as implemented in QMPRPlus [39]. In general, we foimd the predictions to... 

The pH dependence of the aqueous solubility was calculated using the ACD Solubility Suite 6.0 program (Advanced Chemistry Development, Toronto Canada), and is shown in Figure 1. It is predicted that although the drug exhibits very low solubility at low pH, its solubility dramatically increases at high pH. 

A classic pharmaceutical science textbook might have defined poor solubility as anything below a solubility of 1 g mL-1 (2 mol L-1 solution for a molecular weight of 500 Da) at pH 6.5 (or pH 7). This classic view is reflected in the Chemical Abstracts SciFinder 2001 solubility range definitions for solubility calculated using Advanced Chemistry Development (ACD) Software Solaris V4.67. These semi-quantitative ranges for molar solubility are very soluble, 1 mol L 1 < solubility soluble, 0.1 mol L 1 < solubility < 1 mol L 1 slightly soluble, 0.01 mol L 1 <... 

The solubility is expressed as logarithm of molar fractions log(S). A recommended partition of the data into training and test sets is also taken from the mentioned paper. Six outliers described in Huanxiang et al. (2005) were removed from the considerations. SMILES notations of organic solvents for this study have been obtained with ACD/ChemSketch software (http //www.acdlabs.com/) according to CAS numbers from US National Library of Medicine (http //toxnet.nlm.nih.gov/). 

While not convincing from a statishcal perspective, the results in this section are consistent with a trend high-activity molecules published in the past decade of medicinal chemistry literature are more likely to be found in the large, hydrophobic and poor solubility corner of chemical property space. These results are not consistent with, for example, cell-based [41] and median-based [42] partihoning of biologically active compounds however, such analyses were performed in the presence of inactive compounds selected from MDDR[41] or ACD [42], with quite probably unrelated chemotypes. ACD, the Available Chemicals Directory [43], and MDDR, the MDL Drug Data Report [43], are databases commonly used by the pharmaceuhcal industry. 

The H-bond belt is incomplete in the aCD molecule, because one glucopyranose unit is in a distorted position. Consequently, instead of the six possible H bonds, only four can be established simultaneously. The yCD is a non-coplanar, more flexible structure therefore, it is the more soluble of the three CDs. 

As would be anticipated for a carboxylic acid, mandelic acid is known to exhibit a pH strong dependence in its aqueous solubility. This pH dependence was calculated using the solubility module of the ACD PhysChem computational program (version 6.0, Advanced Chemistry Development, Toronto, Canada), and these results are plotted in Figure 1. The results indicate that mandelic acid will be freely soluble in basic solution, which would be interpreted to imply that the sodium salt would be freely soluble as well. 

Figure 8-7. ACD prediction versus HPLC experimental results for the solubility of a basic compound.

In preparative chromatography the systems are mainly operated at high feed solubilities and thus thermodynamic effects dominate. If separations with low feed solubilities have to be operated, high-efficiency adsorbents should be used and the ACD injection technique could be applied (Section 4.3.1.1). 

To access the usefulness of the developed model, the overall solubility for the compounds within the World Drug Index (WDI) [64] and the Available Chemical Directory (ACD) [63] databases were calculated. After filtering both databases with the same criteria as used for datasets A and B, the aqueous solubility of the remaining compounds were predicted. To... 

Contact dermatitis can occur from exposure to cement and has been considered an occupational hazard for construction workers (Turk and Rietschel 1993 Roto et al. 1996 Zachariae et al. 1996). The problem develops because chromium(VI)-con-taining residues from blast furnaces are incorporated into cement. Some countries add ferrous sulfate to cement to reduce the amount of soluble hexavalent chromate in the product (Turk and Rietschel 1993 Roto etal. 1996 Zachariae etal. 1996). In the UK, chromium and chromates accounted for 8.1% of the allergic contact dermatitis cases (Meyer et al. 2000). In Finland, chromium causes 5.6% of ACD, with tanners, cast concrete workers, leader goods workers, and metal plating/coating workers being at greatest risk (Kanerva et al. 2000). In Denmark, the chromium(VI) content of 35% of... 

Colorless, highly hygroscopic crystals. M.p. 446°C, b.p. 624°C d 4.736. Solubility (18°C) 432 g. (100 C) 510 g. (anhydrous salt)/100 ml. HsO. Below 0°C, Znig 2H3O crystallizes out of solution. Soluble in ethanol, ether, acetone and dioxane. Sublimes in vacuum (crystal needles). Decomposes on heating in air. Crystal structure tetragonal space group I4x /acd. 

ACD Labs database Morvary J, Gyongysi J and Kiss L, Determination of the pKg value of ethinyl estradiol on the basis of its solubility, Acta Pharm. Hung., 50, 243-247 (1980). NB A gas-liquid chromatographic method was used to measure the very low solubilities of ethinyl estradiol in buffers of varying pH, to determine its pKg value of 10.32. This was similar to the value obtained using a spectrophotometric method. 

The aCD, pCD, and HPpCD were used to increase the solubility of a range of plant-derived EO compounds (carvacrol = Carv, eugenol = Eng (EG), linalool = Lin and 2-pentanoylfuran = Pentfuran) and its influence on the antimicrobial activity of EO components on a range of microorganisms was tested. 

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