Previously, it was reported that one group of propolis (Group 12) was identified in southeastern Brazil, and the botanical origin of the propolis was Baccharis dracunculifolia resinous exudates. It was also observed that honeybee (Africanized Apis mellifera) mainly visited the leaf buds or unexpanded leaves of B. dracunculifolia but rarely expanded leaves. B. dracunculifolia is dioecious with male and female inflorescences, and RPHPLC of the ethanolic extracts of the respective male and female bud resinous exudates showed the same profiles. RPHPLC profiles of propolis G12 leaf buds and unexpanded and expanded leaves of B. dracunculifolia showed similarity, but unexpanded leaves quantitatively decreased in chemical constituents as compared with leaf buds. In the case of expanded leaves, all chemical constituents were severely decreased or disappeared. Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) was also identified in both propolis and resinous exudates, and both ethanolic extracts contained the highest concentrations of this compound as compared with the rest of the chemical constituents.

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The hydrogen and fluorine nmr spectra of the fluorine bihalide ions FHX~( X = F, Cl, Br, and I) complete our study of the ten bihalide ions in aprotic solvents. The H-F coupling constant has been resolved in all four fluorine bihalides. Exchange of fluorine is slow; exchange of the other halogens is fast on the nmr time scale. The formation and interconversion equilibria may be adequately interpreted by assuming quantitative hydrogen transfer to the most basic (the smallest) halide ion in the system. Consistent with this, we find that the predominant complex in a solution of HC1 and excess Bris ClHBrnot BrHBras previously reported (Fujiwara and Martin, J. Chem. Phys., 56, 4091 (1972)); the proton shieldings in these ions are coincidentally the same. A heterobihalide ion XHYbehaves as an anion-molecule H-bonded complex XH • • • Y-, where is less than . A simple electrostatic interpretation of the charge shifts on H bonding appears adequate to account for the observed formation constants and hydrogen shieldings. It is possible to make predictions of the bond lengths

Complexation-induced chemical shifts and diffusion coefficients (HR-DOSY) of enantiomers with native and derivatized cyclodextrins were used for calculations of the apparent binding constants of three cyclohexanone inclusion complexes. Correlations between these data and high-performance liquid chromatography were established, revealing that this approach can be applied as an alternative method to predict enantiomeric discrimination.

. Can. J. Chem. 55,2396 (1977).A systematic investigation has been made of some lyotropic mesophases (lyomesophases) which macroscopically orient in magnetic fields. These mesophases have been classified into type I which have a positive diamagnetic anisotropy (AX > 0) and type I1 with AX < 0. The mesophase behavior has been observed as a function mainly of electrolyte additions to binary and ternary systems. The electrolyte has a profound effect on the mesophase behavior at extremely low concentrations. It has the effect in the ternary system, sodium decylsulphate/ decanol/water, of converting a type I to a type I1 mesophase with less than 1 wt.% electrolyte.The addition of electrolytes to binary surfactantlwater systems had the effect of increasing the mesomorphic region to higher water concentrations. I n the case of sodium and cesium decylsulphate, and potassium laurate, these ternary mesophases were of type I and for decylammonium chloride of type 11. The method used to distinguish mesophases and determine the degrees of order of water and some hydrocarbon chain segments has been deuterium magnetic resonance. DOUGLAS M. CHEN, FRED Y. FUJIWARA et LEONARD W. REEVES. Can. J. Chem. 55,2396(1 977).On a fait une ttude systematique de quelques mesophases lyotropes (1yomCsophases) qui s'orientent d'une f a~o n n~acroscopique dans les champs magnttiques. On a classifit ces mtsophases en type I, celles qui ont une anisotropie diamagnetique positive (AX > 0), et type 11, pour celles ou AX < 0. On a principalement observe le comportement de la mesophase en fonction de I'addition d'tlectrolytes a des systtmes binaires et tertiaires. L'electrolyte a un effet considerable sur le comportement de la mesophase a des concentrations extrCmement basses. Sur le systeme tertiaire, decylsulphate de sodium/decanol/eau, l'electrolyte a comme effet de transformer une mesophase de type I en une mtsophase de type I1 avec moins que 1% en poids d'electrolyte. L'effet de l'addition d'tlectrolytes a des systtmes binaires, agent actif a la surfaceleau, est de dkplacer la region mtsomorphe vers des concentrations d'eau plus tlevees. Dans le cas des dtcylsulphates de sodium et de ctsium et du laurate de potassium, les phases ternaires sont du type I alors que pour le chlorure de dCcylammonium elle est du type 11. On utilise la resonance magnetique d u deuterium comme mtthode pour distinguer les mesophases et pour determiner les degrts d'ordre de l'eau et de quelques segments de chaines hydrocarbones.[Traduit par le journal] Introduction in any given system (4-8). In the most thorough l-he complex superstructures of lyotropic studies these mesophases are characterized by mixtures of amphiphilic compounds, in water, their low angle X-ray diffraction Pattern. LYOformed ill the regime of concentrated micellar mesophases which can be oriented either spansystems, lead to liquid crystalline properties of taneously or by means the resulting fluids (I). These lyoniesophases are advantages for study by any technique where important both with reference ...