Apparent molal volumes, [Formula: see text], of secondary and tertiary amines and linear hydrocarbons were determined in benzene at 25 °C, using a vibrating tube densimeter. These quantities have been extrapolated to infinite dilution to obtain partial molal volumes. The contribution to partial molal volume of the amine groups, calculated using a simple additive scheme, [Formula: see text], were interpreted in terms of conformational effects present in these molecules. A first attempt to find a measure of the contribution to the partial molal volume of the specific interaction amine–benzene in tertiary and secondary amines was made. The results agree well in the two different approaches used.

Octyl and dodecyl glycosides possessing 2-deoxy-arabino-hexopyranoside moieties belonging to the D-and L-series in their alpha-and beta-forms were synthesized by reaction of an acetyl protected glycal with octanol or dodecanol, catalyzed by triphenylphosphine hydrobromide, followed by deprotection. Their surface properties were studied and discussed in terms of the adsorption and aggregation parameters, pC(20), CMC, and gamma(CMC). The antimicrobial activities were assessed using the paper disk diffusion and broth dilution methods. Both the octyl and dodecyl 2-deoxy beta-D-glycosides inhibited significantly Enterococcus faecalis, a microbe also highly susceptible to dodecyl 2,6-dideoxy-alpha-L-arabino-hexopyranoside. This compound was particularly active against Bacillus cereus and Bacillus subtilis, presenting for both Bacillus species a minimal inhibitory concentration of the same order of magnitude and a minimal lethal concentration even smaller than that obtained for chloramphenicol, a bioactivity which remained unaltered after 1 year solution storage at 4 degrees C. In addition, activity over Listeria monocytogenes was also observed. Direct cytotoxicity and genotoxicity of the glycosides were determined by proliferative index (mitotic index) evaluation in peripheral human lymphocytes of healthy donors. All compounds induced acute toxicity effects, and the response was dose dependent for the alpha-anomer of both the alkyl 2-deoxy-arabinohexopyranosides and for the corresponding dodecyl beta-anomer, what suggests that nontoxic but still bioactive concentrations may be found for these compounds.

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