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The esters of hydroxycinnamic acids in more than 300 species out of 55 genera of Labiatae are investigated. The following compounds have been proved: the caffeic-, 1-caffeyl-, chlorogenic-, cryptochlorogenic-, neochlorogenic-, rosmarinicisochlorogenic-acid as well as the 1-caffeyl-, 6-caff eyl-and 1,6-dicaffeyl-glucose esters. The distribution of the derivatives of the hydroxycirznamic acids and especially of the rosmarinic-acid and the depsides of the caffeic-and quinic-acid may be of taxonomic importance. Zusammenfassttng Es wird ein kurzer Oberblick iiber den derzeitigen Stand der Erforschtrng der ,,GerbstoffeM und der Abkommlinge der Oxyzimtsauren in Labiaten gegeben. Die Ester der Oxyzimtsauren in mehr als 300 Arten aus 55 Gattungen wurden untersucht. Es wurden Kaffee-, 1-Kaffeyl-, Chlorogen-, Kryptochlorogen-, Neochlorogen-, Rosmarin-und lsochlorogensauren, die Ester der Kaffeesaure mit Glukose (die I-Kaffeyl-, 6-Kaffeyl-und 1,6-Dikaffeylglucose) sowie die Abkommlinge der p-Oxyzirnt-und Ferulasauren entdeckt. Auf Grund der Verteilung der Derivate der Oxyzimtsaztren and, besonde.rs, d e~ Rosmarinsaure und der Depside der Kaffee-und Chinasaure wird deren chemotaxonomische Bedeutung fur die Labiaten diskutiert.

Enthalpy and entropy of adsorption of light hydrocarbons C1-C4 have been measured for three monoliths of different polarity and for five different carrier gases: helium, hydrogen, nitrogen, carbon dioxide and dinitrogen oxide. Using carrier gas helium the highest values of enthalpy and entropy were observed for monolith based on ethylenedimethacrylate and the lowest values were observed for monolith based on silica, while monolith based on divinylbenzene demonstrated intermediate values. Entropy-enthalpy correlations were observed with carrier gas helium for all thee monoliths and possess similar slope indicating similar adsorption mechanism on all monoliths studied. Comparing different carrier gases entropy-enthalpy correlations within a homological series of solutes were observed for light carrier gases (He, H2 and N2) and were not observed for heavy carrier gases (CO2 and N2O). Instead, entropy-enthalpy correlations for heavy carrier gases were observed with pressure as variable and the higher the carrier gas pressure the lower the values of enthalpy and entropy observed. The observed changes in entropy-enthalpy correlations were explained by competitive adsorption of heavy carrier gas on monoliths.