Defensive substances from the frontal gland secretion of Nasutitermes nigriceps termite soldiers

1991 ◽  
Vol 56 (12) ◽  
pp. 2969-2977 ◽  
Author(s):  
Irena Valterová ◽  
Miloš Buděšínský ◽  
Jan Vrkoč
Keyword(s):  
Detailed Analysis ◽  
Infrared Spectra ◽  
Nmr Spectra ◽  
Gland Secretion ◽  
Volatile Fraction ◽  
Termite Species ◽  
Frontal Gland ◽  
Derivatives Of ◽  
Termite Soldiers ◽  
C Nmr

The components of the defence secretion of the soldiers of Nasutiterms nigriceps termite species (Isoptera: Termitidae: Nasutitermitinae) have been identified. In the volatile fraction the following components were found: α- and β-pinene, camphene, myrcene, α-terpinene, p-cymene, limonene and terpinolene. Ten diterpenic compounds (I - X), mostly derivatives of the tricyclic trinervitane, were found in the non-volatile fraction. The structure of the so far undescribed 1(15),8(19)-trinervitadiene-2β,3α,14α-triol triacetate (X) was determined on the basis of its mass and infrared spectra and a detailed analysis of 1H and 13C NMR spectra. Considerable differences were found in the composition of the non-volatile fraction of the secretion of the species of termites studied from various localities.

NMR Determination of the Structure of Peracetylated Icariside B2 from Veratrum Lobelianum BERNH.

1995 ◽  
Vol 60 (8) ◽  
pp. 1380-1385 ◽  
Author(s):  
Václav Suchý ◽  
Miloš Buděšínský ◽  
Karel Ubik ◽  
Daniel Grančai ◽  
Vlasta Földešiová
Keyword(s):  
Detailed Analysis ◽  
Nmr Spectra ◽  
Aerial Part ◽  
C Nmr

rel(1S,4S,5R)-3,3,5-Trimethyl-4-[( 1E)-3-oxo-1-butenyl]-4,5-epoxy-cyclohexyl-O-β-D-glucopyranoside (I) was isolated from the aerial part of Veratrum lobelianum BERNH. The structure was derived mainly from detailed analysis of 1H and 13C NMR spectra of its acetylated derivative II. Compound I has been already reported under the name icariside B2in Epimedium grandiflorum MORR. var. thunbergianum (MIQ.) NAKAI.

Preparation of 2,3-Dideoxy-2,3-epimino and 3,4-Dideoxy-3,4-epimino Derivatives of 1,6-Anhydro-β-D-hexopyranoses by Mitsunobu Reaction

1998 ◽  
Vol 63 (6) ◽  
pp. 813-825 ◽  
Author(s):  
Jiří Kroutil ◽  
Tomáš Trnka ◽  
Miloš Buděšínský ◽  
Miloslav Černý
Keyword(s):  
Nmr Spectra ◽  
Mitsunobu Reaction ◽  
Derivatives Of ◽  
C Nmr

A series of new 2-, 3- and 4-benzylamino-2-, 3- and 4-deoxy derivatives of 1,6-anhydro-β-D-hexopyranoses were prepared from 1,6:2,3- and 1,6:3,4-dianhydro-β-D-hexopyranoses by treatment with benzylamine and converted into 2,3-(N-benzylepimino)-2,3-dideoxy- and 3,4-(N-benzylepimino)-3,4-dideoxy-β-D-hexopyranoses of the D-allo, D-galacto and D-talo configuration by Mitsunobu reaction. The structures of benzylamino and benzylimino derivatives were confirmed by 1H and 13C NMR spectra.

Alkylated benzimidazole and benzotriazole derivatives of 3-amino-2-propenoic acid

1989 ◽  
Vol 54 (3) ◽  
pp. 713-724 ◽  
Author(s):  
Viktor Milata ◽  
Dušan Ilavský ◽  
Igor Goljer
Keyword(s):  
Hydrogen Atom ◽  
Nmr Spectra ◽  
Model Compounds ◽  
Methyl Group ◽  
Propenoic Acid ◽  
Independent Synthesis ◽  
Amino Derivatives ◽  
Derivatives Of ◽  
Benzotriazole Derivatives ◽  
C Nmr

The alkylation of unsubstituted 3-(5-benzimidazolyl- and 5-benzotriazolyl)amino derivatives of 2-propenoic acid (I) results in the replacement of hydrogen atom at the nitrogen of YZC=CH-NH- substituent (II-IV). The model compounds with a methyl group in the azole nucleus (V-VII) have been prepared by an independent synthesis. The structure of all products has been confirmed and confronted with their IR, UV, 1H and 13C NMR spectra.

scholarly journals Synthesis and Characterization of Zinc(II)-Complexes with S-Alkyl Derivatives of Thiosalicylic Acid

2018 ◽  
Vol 19 (2) ◽  
pp. 113-117 ◽  
Author(s):  
Milos V. Nikolic ◽  
Marina Z. Mijajlovic ◽  
Dusan Lj. Tomovic ◽  
Andriana M. Bukonjic ◽  
Verica V. Jevtic ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Ethanol Solution ◽  
Alkyl Halides ◽  
Synthesis And Characterization ◽  
Direct Reaction ◽  
Thiosalicylic Acid ◽  
Alkyl Derivatives ◽  
Derivatives Of ◽  
C Nmr

Abstract New zinc(II)-complexes with S-alkyl derivatives of thiosalicylic acid (alkyl = benzyl-(L1), methyl-(L2), ethyl-(L3), propyl-(L4), butyl-(L5)) have been synthesized and characterized by elemental microanalysis, IR spectroscopy, and 1H and 13C NMR spectroscopy. The S-alkyl derivatives of thiosalicylic acid were prepared by alkylation of thiosalicylic acid by adding alkyl halides to an alkaline water-ethanol solution, while the corresponding zinc(II)-complexes were obtained via the direct reaction of ZnCl2 with S-alkyl derivatives of thiosalicylic acid in water. Based on the microanalysis results and the IR and NMR spectra of the S-alkyl derivatives of thiosalicylic acid and the corresponding zinc(II)-complexes, we concluded that the ligands are bidentately coordinated to the zinc(II)-ion.

Coordination compounds of indium. Part 44. The oxidation of indium(I) halides by tetrahalogeno-ortho-quinones

1988 ◽  
Vol 66 (11) ◽  
pp. 2935-2940 ◽  
Author(s):  
Theodore A. Annan ◽  
Dennis G. Tuck
Keyword(s):  
Coordination Compounds ◽  
Nmr Spectra ◽  
Dynamic Behaviour ◽  
Addition Product ◽  
Donor Ligands ◽  
Chelate Complexes ◽  
H Nmr ◽  
Anionic Complexes ◽  
Derivatives Of ◽  
C Nmr

The reaction of indium(I) halides (InX; X = Cl, Br, I) with tetrahalogeno-ortho-quinones (Y4C6O2; Y = Cl, Br) gives the oxidative addition product Y4C6O2InX, These compounds have been isolated as adducts with neutral bidentate donor ligands (N,N,N′,N′-tetramethylethanediamine (tmen), 1,10-phenanthroline) or as salts of the anionic complexes [Y4C6O2InCl2]− or [Y4C6O2In(Cl)Br]−. The number of coordinated tmen molecules, and hence the structure, depends on the method of preparation. Infrared, 1H NMR, and 13C NMR spectroscopy all confirm that these products are all substituted-catecholato derivatives of indium(III), and the structure of these various neutral or anionic derivatives is discussed. The temperature dependence of the 13C NMR spectra shows that the dynamic behaviour of these compounds (in d6-dmso) is similar to that observed in previous studies of indium(III) chelate complexes.

Conformation of dimethylaminoethanol, its methyl ether and of the corresponding trimethylammonium iodides. NMR and vibrational spectra

1987 ◽  
Vol 52 (5) ◽  
pp. 1256-1271 ◽  
Author(s):  
Jan Štokr ◽  
Bohdan Schneider ◽  
Danica Doskočilová ◽  
Stanislav Ševčík ◽  
Martin Přádný
Keyword(s):  
Methyl Ether ◽  
Infrared Spectra ◽  
Vibrational Spectra ◽  
Crystalline State ◽  
Nmr Spectra ◽  
H Nmr ◽  
Liquid States ◽  
Fully Coupled ◽  
Solid And Liquid States ◽  
C Nmr

By analysis of fully coupled 13C NMR spectra and of 1H NMR spectra of dimethylaminoethanol, its methyl ether, and of the corresponding trimethylammonium iodides, populations of isomers generated by rotation about the bonds N-CH2, CH2-CH2, and CH2-O in these compounds in solution were determined. By analysis of Raman and infrared spectra of these compounds in the solid and liquid states it was found that in the crystalline state these compounds form structures with parallel N-CH3 and O-CH2 bonds, which are also preferred in the liquid state.

Amino-acid zwitterion equilibria: vibrational and nuclear magnetic resonance studies of methyl-substituted thiazolidine-4-carboxylic acids

1986 ◽  
Vol 64 (6) ◽  
pp. 1215-1219 ◽  
Author(s):  
H. E. Howard-Lock ◽  
C. J. L. Lock ◽  
M. L. Martins ◽  
P. S. Smalley ◽  
R. A. Bell
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Amino Acid ◽  
Magnetic Resonance ◽  
Infrared Spectra ◽  
Nmr Spectra ◽  
Infrared And Raman Spectra ◽  
Solid Samples ◽  
Magnetic Resonance Studies ◽  
Cysteine Hydrochloride ◽  
C Nmr

Infrared and Raman spectra (4000–100 cm−1) of solid samples of six different methyl substituted thiazolidine products of D-penicillamine and L-cysteine hydrochloride have been observed and assigned. Infrared spectra in D2O solutions have been obtained for comparison in order to study the amino-acid zwitterion equilibria. Proton and 13C nmr spectra for the compounds have also been measured.

Acryloyloxy and methacryloyloxy derivatives of phenylacetic acid and their polymers

1987 ◽  
Vol 52 (6) ◽  
pp. 1494-1500 ◽  
Author(s):  
František Hrabák ◽  
Milan Bezděk ◽  
Jan Lokaj ◽  
Hana Pivcová ◽  
Vladimír Kubánek
Keyword(s):  
Nmr Spectra ◽  
Phenylacetic Acid ◽  
Melting Points ◽  
Derivatives Of ◽  
C Nmr

2-Methacryloyloxy-2-phenylacetic acid (I), 2-acryloyloxy-2-phenylacetic acid (II), 4-methacryloyloxyphenylacetic acid (III), and 4-acryloyloxyphenylacetic acid (IV), ethyl 4-methacryloyloxyphenylacetate (V) and ethyl 4-acryloyloxyphenylacetate (VI) were prepared. The new monomers were characterized by their melting points, IR, 1H and 13C NMR spectra; their polymerization was also examined.

29Si (and 13C) NMR spectra of modified silatranyl derivatives of some monosaccharides

1984 ◽  
Vol 49 (12) ◽  
pp. 2897-2902 ◽  
Author(s):  
Jan Schraml ◽  
Aleksandr Mikhailovich Krapivin ◽  
Aleksandr Petrovich Luzin ◽  
Vladimir Mikhailovich Kilesso ◽  
Vadim Aleksandrovich Pestunovich
Keyword(s):  
Molecular Structure ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Distinct Advantage ◽  
13C Nmr Spectra ◽  
Limited Data ◽  
Structural Sensitivity ◽  
Trimethylsilyl Derivatives ◽  
Derivatives Of ◽  
C Nmr

29Si (and 13C) NMR chemical shifts are reported for several 2-carba-3-oxahomosilatranyl (3,9,10-trioxa-6-aza-1-silabicyclo[3.3.4]dodecane-1-yl) and silatranyl (2,8,9-trioxa-5-aza-1-silabicyclo[3.3.3]undecane-1-yl) derivatives of some monosaccharides and other alcohols. The limited data suggest somewhat larger sensitivity of the silicon chemical shifts to molecular structure in 2-carba-3-oxahomosilatranyl derivatives than in silatranyl derivatives. In comparison with trimethylsilyl derivatives homosilatranyl derivatives show lower structural sensitivity of the silicon chemical shift. In some cases, however, larger stability of the silatranyl or 2-carba-3-oxahomosilatranyl derivatives than that of trimethylsilyl derivatives might be a distinct advantage.

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