Experimental vapor pressures, vaporization, fusion and sublimation enthalpies of a number of dialkyl benzenedicarboxylates have been examined by correlation gas chromatography (CGC) experiments in order to identify a series of experimental measurements that appear to be internally self-consistent. The compounds studied in this regard include dimethyl phthalate dimethyl terephthalate, dimethyl isophthalate, diethyl phthalate, dibutyl phthalate, and bis(2-ethylhexyl) phthalate. New vaporization enthalpies and liquid vapor pressure equations (T/K = 298.15 to 550) of several other compounds are reported also evaluated by CGC experiments. The compounds, the vaporization, fusion, and sublimation enthalpies and liquid and solid vapor pressures evaluated are summarized in Table 22 of the text.

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The first synthesis of the repeating unit of S. aureus capsular polysaccharide type 8 is described. The repeating unit is an unusual trisaccharide sequence of three uncommon sugars, all connected via 1,2-cis linkages. The synthetic trisaccharide was equipped with capping methyl groups at the points of propagation of the polysaccharide sequence.

The profound effect of substituents at C-5 of glycosyl sialosides on their stereoselectivity is well-known although the exact nature of this effect is somewhat less understood. Presented herein is a comparative study of a range of novel sialyl donors with various O-substituents. It is demonstrated that O-substituents at C-4 and C-7 may also have a significant effect on the reactivity of sialyl donors and on the stereoselectivity of chemical sialylation.

Vapor pressures, vaporization, and sublimation enthalpies of several pharmaceuticals have been evaluated by a combination of correlation chromatography experiments, differential calorimetry measurements with existing literature values. The compounds investigated and their properties include 1-adamantylamine [Δcr l H m(T fus)/kJ·mol–1 = (7.3 ± 0.2); T fus/K = (477.4 ± 0.9); Δl g H m(298.15 K)/kJ·mol–1 = (59.9 ± 2.5); Δcr g H m(298.15 K)/kJ·mol–1 = (∼59.9 ± 3.5); p (l)/Pa = (21 ± 1); p (cr)/Pa = (11.5 ± 2.1)]; 1-adamantyl-ethanamine, [Δl g H m(298.15 K)/kJ·mol–1 = (68.7 ± 3.7); p (l)/Pa = (3 ± 1)]; α,α-dimethylphenethylamine [Δl g H m(298.15 K)/kJ·mol–1 = (60.2 ± 2.6); p (l)/Pa = (35 ± 4)]; trans 2-phenylcyclopropylamine [Δl g H m(298.15 K)/kJ·mol–1 = (60.3 ± 2.1), p (l)/Pa = (28 ± 5)]; 1-dodecanamine [Δcr g H m(298.15 K)/kJ·mol–1 = (118.3 ± 1.8); p (cr)/Pa = 1.6 ± 0.1]; and 1-tetradecanamine [Δcr g H m(298.15 K)/kJ·mol–1 = (134.5 ± 2.1); p (cr)/Pa = 0.12 ± 0.04]. Vapor pressure equations also derived from vapor pressureretention time correlations as a function of temperature are reported for both standards and targets. The equations appear applicable from T/K = 298.15 to each compound’s respective boiling temperature.

We previously reported that the selective activation of an Sbenzoxazolyl (SBox) sialyl donor over a galactosyl acceptor equipped with a thioethyl anomeric moiety can be performed in high yield but with poor stereoselectivity. To optimize this strategy, which allows the synthesis of complex carbohydrates to be shortened, a range of SBox sialyl donors modi-

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The vaporization enthalpies and liquid vapor pressures at T/ K = 298.15 have been evaluated by correlation gas chromatography for the following fatty acids (Δ l g H m (298.15 K)/kJ•mol −1 ; 10 8 •p l 298 /Pa): (9Z)hexadecenoic acid (palmitoleic acid) (123.0 ± 6.4); (6900 ± 4200), (6Z)octadecenoic acid (petroselinic acid), (131.2 ± 2.1); (1130 ± 1000), (9Z)octadecenoic acid (oleic acid), (132.6 ± 6.6); (1010 ± 600), (5Z,8Z,11Z,14Z)-eicosatetraenoic acid (arachidonic acid), (145.3 ± 6.8); (65 ± 37), (11Z)-eicosenoic acid (gondoic acid), (143.5 ± 2.2); (118 ± 105), (4Z,7Z,10Z,13Z,16Z,19Z)-docosahexenoic acid (cervonic acid), (162.9 ± 2.3); (2.2 ± 2.0), (15Z)-tetracosenoic acid (nervonic acid), (170.6 ± 2.3), (1.0 ± 0.9); n-tetracosanoic acid (lignoceric acid), (170.7 ± 2.3); (1.1 ± 1.0), and n-hexacosanoic acid (cerotic acid, (177.2 ± 2.4); (0.25 ± 0.22). For those fatty acids that are solids at T/K = 298.15, the following fusion temperatures, fusion and sublimation enthalpies, and solid vapor pressures are also reported (T fus /K; Δ cr l H m (T fus )/kJ• mol −1 ; Δ cr g H m (298.15 K)/kJ•mol −1 ; 10 10 •p cr 298 /Pa): (15Z)-tetracosenoic acid (315 ± 0.3); (60.3 ± 0.5), (228.9 ± 2.4), 27; tetracosanoic acid (356.5 ± 0.2); (84.5 ± 0.5); (253 ± 3.2), 0.4, hexacosanoic acid (358.8 ± 0.3); (88.5 ± 1.0); (257.8 ± 3.5), 0.08. Vapor pressures of the solids are believed accurate within a factor of 3. Tetracosanoic acid also exhibited phase transitions: T/K = (347 and 351); (4.94 ± 0.1) kJ•mol −1 . The phase transition for hexacosanoic at T/K = (354.3 ± 0.1) was not resolved from the fusion peak; the enthalpy is included in the fusion enthalpy. Equations to evaluate liquid vapor pressures for a series of saturated and unsaturated fatty acids from T/K = (298.15 to T b ) are also derived.