400MHz H-NMR spectra of amino acids.

Abstract Persimmons are a traditional, autumnal, and healthy fruit commonly consumed in Japan and East Asia based on the saying, “a persimmon a day keeps the doctor away.” The differences in metabolites among five major Japanese persimmon cultivars were investigated using a nuclear magnetic resonance (NMR)-based metabolomics approach. By using a broadband water suppression enhanced through T1 effects (WET) method for the sensitive detection of minor metabolites, better discrimination among cultivars and more informative details regarding their metabolic differences have been achieved compared to those achieved in conventional 1H NMR sequences. Among the nonastringent cultivars analyzed, the Taishu cultivar has the highest abundance of amino acids. The Matsumotowase-Fuyu cultivar contains ethyl-β-glycosides as characteristic components, which may relate to fruit softening. Citric acid concentration is higher in Maekawa Jiro than in other nonastringent cultivars. Among the two astringent cultivars analyzed, ethanol was significantly higher in Hiratanenashi than in Yotsumizo, which indicates different reactivity during deastringency treatments. The present study proposes an efficient and relatively quantitative metabolomics approach based on broadband WET NMR spectra.

Download Full-text

Conformational structure of ethylene glycol dibenzoate. Vibrational and NMR spectra

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811913 ◽

1981 ◽

Vol 46 (8) ◽

pp. 1913-1929 ◽

Cited By ~ 3

Author(s):

Bohdan Schneider ◽

Pavel Sedláček ◽

Jan Štokr ◽

Danica Doskočilová ◽

Jan Lövy

Keyword(s):

Ethylene Glycol ◽

Vibrational Spectra ◽

Nmr Spectra ◽

Coupling Constants ◽

Conformational Structure ◽

Infrared And Raman Spectra ◽

H Nmr ◽

Liquid States ◽

Crystalline Forms ◽

C Nmr

It was found that three crystalline forms of ethylene glycol dibenzoate can be prepared. Infrared and Raman spectra of these three forms, as well as of the glassy and liquid states, were measured. From 3JHH coupling constants obtained by analysis of the 13C satellite band of the -CH2- group in 1H NMR spectra, and from the 3JCH coupling constants of the -CO.O.CH2- fragment obtained by analysis of the carbonyl band in 13C NMR spectra it was found that in the liquid state the -CH2-CH2- group exists predominantly in the gauche conformational structure, and the bonds C-O-C-C assume predominantly a trans orientation. The results of the analysis of NMR and vibrational spectra were used for the structural interpretation of conformationally sensitive bands in vibrational spectra of ethylene glycol dibenzoate.

Download Full-text

Preparation and absolute configuration at C(20) of 21-nor-5α-chol-22-en-24→20-olide derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810917 ◽

1981 ◽

Vol 46 (4) ◽

pp. 917-925 ◽

Cited By ~ 2

Author(s):

Vladimír Pouzar ◽

Miroslav Havel

Keyword(s):

Absolute Configuration ◽

Nmr Spectra ◽

Lithium Salt ◽

H Nmr ◽

Chemical Correlation ◽

Unsaturated Lactones

Reaction of the aldehyde I with the lithium salt of 1-(2-tetrahydropyranyloxy)-2-propyne yielded the compounds II and IV. From the compound II the lactone XII was prepared via the intermediates III and X, the lactone XVIII was prepared from the substance IV via the intermediates V and XVI. The unsaturated lactones XII and XVIII were also prepared by sulfenylation and dehydrosulfenylation of the saturated lactones XIII and XIX. Based on chemical correlation and 1H-NMR spectra analyses of the compounds II and IV, the lactone XII was assigned the 20R-configuration whereas the lactone XVIII was allotted the 20S-configuration.

Download Full-text

New type of addition to 5-substituted 4-arylidene-2-(4,5-dihydrofurfurylidene)-N,N-dimethyliminium bisperchlorates. Preparation of 4-substituted 5-(N,N-dimethylamino)-2-furancarbaldehydes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860573 ◽

1986 ◽

Vol 51 (3) ◽

pp. 573-580 ◽

Cited By ~ 3

Author(s):

Tibor Gracza ◽

Zdeněk Arnold ◽

Jaroslav Kováč

Keyword(s):

Nmr Spectra ◽

Addition Reaction ◽

H Nmr ◽

Organic Bases ◽

New Type

4-Arilidene-5-(N,N-dimethyliminium)-2-(4,5-dihydrofurfurylidene)-N,N-dimethyliminium bisperchlorate I undergoes a 1,4-addition reaction with organic bases under re-formation of the furan nucleus; this behaviour has been utilized in the preparation of new 4-substituted 5-(N,N-dimethylamino)-2-furancarbaldehydes II, III. The structure of the prepared compounds has been confirmed by 13C and 1H NMR spectra.

Download Full-text

Preparation, properties and structure of some intermediate nido- and arachno-monocarbaboranes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19812345 ◽

1981 ◽

Vol 46 (10) ◽

pp. 2345-2353 ◽

Cited By ~ 33

Author(s):

Karel Baše ◽

Bohumil Štíbr ◽

Jiří Dolanský ◽

Josef Duben

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Nmr Spectra ◽

Liquid Ammonia ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Starting Compound

The 6-N(CH3)3-6-CB9H11 carbaborane reacts with sodium in liquid ammonia with the formation of 6-CB9H12- which was used as a starting compound for preparing the 4-CB8H14, 9-L-6-CB9H13 (L = (CH3)2S, CH3CN and P(C6H5)3), 1-(η5-C5H5)-1,2-FeCB9H10-, and 2,3-(η5-C5H5)2-2,31-Co2CB9H10- carboranes. The 4-CB8H14 compound was dehydrogenated at 623 K to give 4-(7)-CB8H12 carborane. Base degradation of 6-N(CH3)3-6-CB9H11 in methanol resulted in the formation of 3,4-μ-N(CH3)3CH-B5H10. The structure of all compounds was proposed on the basis of their 11B and 1H NMR spectra and X-ray diffraction was used in the case of the transition metal complexes.

Download Full-text

The preparation of 3-amino-3-deoxy-1,2-O-isopropylidene-α-L-erythrofuranose, 3-amino-3-deoxy-1,2-O-isopropylidene-β-D-threofuranose and their derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19803378 ◽

1980 ◽

Vol 45 (12) ◽

pp. 3378-3390 ◽

Cited By ~ 3

Author(s):

Jiří Jarý ◽

Milena Masojídková ◽

Ivan Kozák ◽

Miroslav Marek ◽

Jan Staněk

Keyword(s):

Nucleophilic Substitution ◽

Sodium Azide ◽

Sodium Benzoate ◽

Nmr Spectra ◽

Subsequent Reduction ◽

H Nmr ◽

Amino Derivatives

The title amino derivatives VI and XIV were prepared by nucleophilic substitution of p-toluenesulfonyl derivatives II and XVII with sodium azide or hydrazine and subsequent reduction. Nucleophilic substitution of compounds II and XVII with sodium benzoate was also investigated. The 1H NMR spectra of the substances prepared are discussed.

Download Full-text

Preparation of (20E)-21-Ethoxycarbonyl-14β,17α-pregna-5,20-dien-3β-yl Hydrogen Butanedioate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950715 ◽

1995 ◽

Vol 60 (4) ◽

pp. 715-718 ◽

Cited By ~ 1

Author(s):

Vladimír Pouzar ◽

Ivan Černý

Keyword(s):

Title Compound ◽

Nmr Spectra ◽

Total Yield ◽

Reaction Sequence ◽

Pregnane Series ◽

H Nmr

The title compound X was prepared according to the recently published procedure for preparation of analogous derivatives in the 5β-pregnane series, using the reaction sequence I -> II -> III -> IV -> V -> VI -> VII -> VII -> IX -> X (total yield 18%). The configuration at ring D centers (14β,17α) follows from the structure of the starting ketone I and was also checked by comparing diol IV with the sample prepared by an independent route. The epimeric purity at C-17 was carefully monitored during the whole synthesis by 1H NMR spectra (singlet of 18-H3).

Download Full-text

119Sn, 13C and 1H NMR Spectra of Tris(1-butyl)stannyl D-Glucuronate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19971169 ◽

1997 ◽

Vol 62 (8) ◽

pp. 1169-1176 ◽

Cited By ~ 2

Author(s):

Antonín Lyčka ◽

Jaroslav Holeček ◽

David Micák

Keyword(s):

Chemical Shift ◽

Carbonyl Group ◽

1H Nmr ◽

Equatorial Plane ◽

Title Compound ◽

Nmr Spectra ◽

Hydroxyl Groups ◽

Carboxylic Group ◽

H Nmr ◽

Oxygen Atoms

The 119Sn, 13C and 1H NMR spectra of tris(1-butyl)stannyl D-glucuronate have been measured in hexadeuteriodimethyl sulfoxide, tetradeuteriomethanol and deuteriochloroform. The chemical shift values have been assigned unambiguously with the help of H,H-COSY, TOCSY, H,C-COSY and 1H-13C HMQC-RELAY. From the analysis of parameters of 119Sn, 13C and 1H NMR spectra of the title compound and their comparison with the corresponding spectra of tris(1-butyl)stannyl acetate and other carboxylates it follows that in solutions of non-coordinating solvents (deuteriochloroform) the title compound is present in the form of more or less isolated individual molecules with pseudotetrahedral environment around the central tin atom and with monodentately bound carboxylic group. The interaction of tin atom with oxygen atoms of carbonyl group and hydroxyl groups of the saccharide residue - if they are present at all - are very weak. In solutions in coordinating solvents (hexadeuteriodimethyl sulfoxide or tetradeuteriomethanol), the title compound forms complexes with one molecule of the solvent. Particles of these complexes have a shape of trigonal bipyramid with the 1-butyl substituents in equatorial plane and the oxygen atoms of monodentate carboxylic group and coordinating solvent in axial positions.

Download Full-text

A 15N, 13C, and 1H NMR study of reaction products from arylguanidines and chloroformate esters

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19911505 ◽

1991 ◽

Vol 56 (7) ◽

pp. 1505-1511 ◽

Cited By ~ 2

Author(s):

Antonín Lyčka ◽

Karel Palát

Keyword(s):

1H Nmr ◽

Nmr Spectra ◽

Reaction Products ◽

H Nmr ◽

Nmr Study

The 15N, 13C, and 1H NMR spectra of the reaction products from arylguanidines with two mols of chloroformate esters have been measured. With application of the corresponding 15N isotopomer it has been proved that the reaction products have the structures IIIa-IIIc.

Download Full-text

15N, 13C, and 1H NMR Spectra of Azo and Hydrazo Compounds Derived from 1,3,3-Trimethyl-2-methylidene-2,3-dihydroindole (Fischer Base)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19981012 ◽

1998 ◽

Vol 63 (7) ◽

pp. 1012-1020 ◽

Cited By ~ 6

Author(s):

Antonín Lyčka ◽

Josef Jirman ◽

Alois Koloničný

Keyword(s):

Double Bond ◽

Hydrochloric Acid ◽

Nmr Spectra ◽

Coupling Constants ◽

Azo Compounds ◽

Passive Component ◽

Geometric Isomers ◽

H Nmr ◽

Fischer Base ◽

Hydrazone Form

The 15N, 13C, and 1H NMR spectra were measured for azo and hydrazo compounds derived from 1,3,3-trimethyl-2-methylidene-2,3-dihydroindole (Fischer base), which is a passive component with a terminal methylidene group. Products prepared by coupling in hydrochloric acid exist in the corresponding hydrazone form as the E-isomers. Neutralization gives a mixture of two isomeric azo compounds which differ in the arrangement at the C(2)=C(10) double bond. This mixture was alkylated with methyl iodide to obtain the =N-N(CH3)- hydrazone derivatives. The geometric isomers were resolved based on the NOESY approach and the stereospecific behaviour of the 2J(15N,13C) coupling constants was studied for the 15N-labelled compounds.

Download Full-text