Search Results - "Vrkoc, Jan"

Exploitation of kairomones and synomones by Medetera spp. (Diptera: Dolichopodidae), predators of spruce bark beetles by Jiri HULCR, Marc POLLET, Karel UBIK, Jan VRKOČ

“…The semiochemical relationships in a predator-prey-host plant system were studied by a series of multiple-choice field assays. The studied system included…”
Get full text

Mirasorvone: a masked 20-ketopregnane from the defensive secretion of a diving beetle (Thermonectus marmoratus) by Meinwald, J. (Cornell University, Ithaca, NY.), Huang, Q, Vrkoc, J, Herath, K.B, Yang, Z.C, Schroder, F, Attygalle, A.B, Iyengar, V.K, Morgan, R.C, Eisner, T

“…The sunburst diving beetle, Thermonectus marmoratus, ejects a milky fluid from its prothoracic defensive glands when disturbed. Two major volatile components…”
Get full text

Volatiles released from oak, a host tree for the bark beetle Scolytus intricatus by Vrkočová, Pavlı́na, Valterová, Irena, Vrkoč, Jan, Koutek, Bohumı́r

“…Volatile compounds emitted in different phases of oak ( Quercus robur) development (bark, unopened buds, young developing leaves, and blossoms) were analyzed…”
Get full text

Gas chromatographic determination of vapour pressures of pheromone-like compounds III. Aldehydes by Koutek, Bohumir, Hoskovec, Michal, Vrkočov, Pavlína, Konečný, Karel, Feltl, Ladislav, Vrkoč, Jan

“…Equilibrium vapour pressures of six saturated and seventy-four mono-unsaturated C 10-C 16 even-carbon aldehydes were determined using a method based on gas…”
Get full text

Structure of 3.alpha.-hydroxy-15-rippertene. Evidence for 1,2-methyl migration during biogenesis of a tetracyclic diterpene in termites by Prestwich, Glenn D, Spanton, Stephen G, Lauher, Joseph W, Vrkoc, Jan

Get full text

A convenient synthesis of trans-sabinene hydrate from (−)-3-thujol via a highly selective ene reaction of singlet oxygen by Baeckström, Peter, Koutek, Bohumir, Šaman, David, Vrkoč, Jan

“…trans-Sabinene hydrate ( 1), was synthesized from (−)-3-thujol ( 2) in four steps. The key step was the selective formation of trans-2-hydroxy-3-thujene ( 6)…”
Get full text

Biotransformations of γ-methyl-β-ketosulfones: stereoselectivity of 3-methyl-1-(phenylsulfonyl)hexan-2-one reductions by various yeasts by Svatoš, Aleš, Huňková, Zdenka, Křen, Vladimír, Hoskovec, Michal, Šaman, David, Valterová, Irena, Vrkoč, Jan, Koutek, Bohumír

“…The stereoselectivity of the reduction of rac-3-methyl-1-(phenylsulfonyl)hexan-2-one ( 1) to 3-methyl-1-(phenylsulfonyl)hexan-2-ol ( 2) diastereomers by more…”
Get full text

Contents and enantiomeric compositions of monoterpene hydrocarbons in xylem oleoresins from four Pinus species growing in Cuba. Comparison of trees unattacked and attacked by Dioryctria horneana by Valterová, Irena, Sjödin, Kristina, Vrkoč, Jan, Norin, Torbjörn

“…Monoterpene hydrocarbons from the xylem oleoresins of Pinus tropicalis, P. caribaea var. caribaea, P. cubensis and P. maestrensis growing in Cuba were…”
Get full text

The enantiomeric composition of monoterpene hydrocarbons in the defensive secretions ofNasutitermes termites (Isoptera): Inter- and intraspecific variations by Valterová, Irena, Vrkoč, Jan, Norin, Tobjörn

Get full text

Kevin c. spencer [ed.] Chemical mediation of coevolution: Academic Press, Inc., San Diego, California, U.S.A. 609 pp by Vrkoč, Jan

Get full text

New mimics of the acetate function in pheromone-based attraction by Hoskovec, Michal, Hovorka, Oldřich, Kalinová, Blanka, Koutek, Bohumír, Streinz, Ludvík, Svatoš, Aleš, Šebek, Pavel, Šaman, David, Vrkoč, Jan

“…Several analogues of ( Z)-8-dodecenyl acetate ( 1a), the major pheromone component of the Oriental fruit moth, Cydia molesta, with chloroformate and lactone…”
Get full text

New Potential Inhibitors of Pheromonal Attractionin the Oriental Fruit Moth, Cydia molesta by Hoskovec, Michal, Hovorka, Oldřich, Kalinová, Blanka, Koutek, Bohumír, Svatoš, Aleš, Šaman, David, Vlček, Kamil, Vrkoč, Jan

“…New analogues of ( Z )-dodec-8-en-1-yl acetate ( Z 8-12:OAc, 1 ), the main sex pheromone component of the Oriental fruit moth, Cydia molesta , were designed by…”
Get full text

Chemical Mediation of Coevolution by Vrkoč, Jan

Get full text

Direct esterification of 2-methoxy-2-phenyl-3,3,3-trifluoropropionic acid: a reinvestigation by SVATOS, A, VALTEROVA, I, SAMAN, D, VRKOC, J

“…The direct esterification of enantiomeric 2-methoxy-2-phenyl-3,3,3-trifluoropropionic acids (MTPA) was reinvestigated. Preferential formation of one of the…”
Get full text

(8Z)-1(15),8(9)-Trinervitadien-3α-ol from Nasutitermes nigriceps termites. The revised structure for a deffense compound of Trinervitermes gratiosus termites by Valterová, Irena, Buděšínský, Miloš, Vrkoč, Jan, Prestwich, Glenn D.

“…The structure of (8 Z )-1(15),8(9)-trinervitadien-3α-ol ( IIa ) was established by a detailed analysis of its NMR spectra for a trinervitane derived alcohol…”
Get full text

Defensive substances from the frontal gland secretion of Nasutitermes nigriceps termite soldiers by VALTEROVA, I, BUDESINSKY, M, VRKOC, J

“…The components of the defence secretion of the soldiers of Nasutiterms nigriceps termite species ( Isoptera: Termitidae: Nasutitermitinae ) have been…”
Get full text

A simple method for estimating vaporization properties of pheromone-like acetates from their molecular structures by KOUTEK, B, HOSKOVEC, M, VRKOC, J

“…A simple computational method has been developed to determine vapor pressures of pheromone-like acetates, This input parameters required, i.e. critical…”
Get full text

Rubber substrates and their influence on isomerization of conjugated dienes in pheromone dispensers by Vrkoc, J. (Czechoslovak Academy of Sciences, Praha, Czechoslovakia), Konecny, K, Valterova, I, Hrdy, I

“…Release rate and degree of isomerization of pheromones with conjugated double bonds were studied in dispensers prepared from several rubber substrates. The…”
Get full text

Determination of the absolute configuration of secondary alcohols by modified Horeau's method using HPLC by SVATOS, A, VALTEROVA, I, FABRYOVA, A, VRKOC, J

“…A method for determination of absolute configuration of secondary alcohols, based on a modified Horeau's method, has been developed. The ratio of (1 R ,2' S )-…”
Get full text

Constituents of frontal gland secretion of peruvian termites Nasutitermes ephratae by VALTEROVA, I, VASICKOVA, S, BUDESINSKY, M, VRKOC, J

“…The defense secretion of Nasutitermes ephratae soldiers was analyzed and its constituents were identified. The volatile fraction contains monoterpenic…”
Get full text