Structure of Dimeric Compounds Obtained from 3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide

1993 ◽  
Vol 58 (7) ◽  
pp. 1675-1691 ◽  
Author(s):  
Eva Klinotová ◽  
Jiří Klinot ◽  
Václav Křeček ◽  
Stanislav Hilgard ◽  
Miloš Buděšínský ◽  
...  
Keyword(s):  
Silica Gel ◽  
Mass Spectra ◽  
Fab Mass Spectra ◽  
C Nmr

The triterpenoid α-diketone with oxabicyclo[2.2.2]octane system in the ring E (3β-acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (I)) gives isopropylidenedioxy derivative II and dimeric compounds V and IX when submitted to chromatography on silica gel in the presence of acetone. Compounds V and IX were reduced with hydride to hydroxy derivatives VI, X, and XI; on reaction with diazomethane they gave dimeric compounds with spiroepoxide group at the position 21 (compound VII) or 22 (compound XII) which reacted further with diazomethane to give monomeric spiroepoxides VIII, XIII, and XIV. The structure of the compounds obtained was derived from their 1H and 13C NMR, IR, and FAB mass spectra.

Synthesis of 2-amino-5,7-dimethyl-4-oxopyrido[3,4-e]-1,3-thiazines

1983 ◽  
Vol 48 (12) ◽  
pp. 3426-3432 ◽  
Author(s):  
Dušan Koščík ◽  
Pavol Kristian ◽  
Ondrej Forgáč
Keyword(s):  
Spectral Data ◽  
Chlorine Atom ◽  
Mass Spectra ◽  
High Reactivity ◽  
Secondary Amines ◽  
Dimroth Rearrangement ◽  
H Nmr ◽  
New Synthesis ◽  
C Nmr

New synthesis of pyrido[3,4-e]-1,3-thiazines consisting in reaction of 2,6-dimethyl-4-chloronicotinoyl isothiocyanate with primary or secondary amines, or with benzaldehyde phenylhydrazone, is described. High reactivity of the chlorine atom does not allow isolation of the corresponding thioureas, arising as intermediates, except in the case of the benzylamino derivative. Structure of the products was unequivocally confirmed by their spectral data (IR, UV, 1H NMR, 13C NMR and mass spectra). The synthesized derivatives do not undergo the Dimroth rearrangement.

Oxynemorensine, an alkaloid from Senecio nemorensis L., var. subdecurrens GRISEB

1980 ◽  
Vol 45 (2) ◽  
pp. 548-558 ◽  
Author(s):  
Antonín Klásek ◽  
Petr Sedmera ◽  
Jindřich Vokoun ◽  
Anna Boeva ◽  
Svatava Dvoráčková ◽  
...  
Keyword(s):  
Unsaturated Acid ◽  
Mass Spectra ◽  
H Nmr ◽  
C Nmr

From S. nemorensis L., var. subdecurrens GRISEB. there were isolated the previously obtained alkaloids nemorensine (I), retroisosenine (II), bulgarsenine (III) and, in addition, the alkaloid oxynemorensine which was assigned the structure VIII on the basis of the interpretation of the 1H-NMR, 13C-NMR, mass spectra, and on that of the identification of the products of hydrolysis and reduction. Furthermore, the isolation of the cis-nemorensic acid (V) as well as that of the unsaturated acid IV, and the transformation of bulgarsenine (III) to nemorensine (I) were described.

The Presence of Disparlure, the Sex Pheromone of the Gypsy Moth, in the Female Nun Moth

1975 ◽  
Vol 30 (9-10) ◽  
pp. 672-675 ◽  
Author(s):  
B. A. Bierl ◽  
Morton Beroza ◽  
V. E. Adler ◽  
G. Kasang ◽  
D. Schneider ◽  
...  
Keyword(s):  
Sex Pheromone ◽  
Silver Nitrate ◽  
Silica Gel ◽  
Gypsy Moth ◽  
Lymantria Dispar ◽  
Mass Spectra ◽  
Sex Attractant ◽  
Chromatographic Retention ◽  
Nun Moth ◽  
Physical And Chemical

Disparlure, (cis-7,8-epoxy-2-methyloctadecane) the sex attractant of the gypsy moth, Porthetria (Lymantria) dispar, attracts the male nun moth, Lymantria monacha, in the field and is a highly effective olfactory stimulus in electroantennogram (EAG) and single-cell recordings. We have now analyzed the extract of 2000 abdominal tips of the female nun moth. Physical and chemical tests, which included gas-chromatographic retention times, elution volumes from silica gel and silica gel-silver nitrate columns, mass spectra, epoxide functionality, EAG-activity of chromatographic fractions with gypsy moth antennae, presence of disparlure precursor, all indicated that disparlure is present in the extract of nun moth sex glands. The optical activity of the natural disparlure of the two species has not yet been determined. Several authors have reported 1-0 that disparlure,

scholarly journals Synthesis, characterization, and antimicrobial activities of novel double-armed benzo-15-crown-5 and their sodium and potassium complexes

2020 ◽  
pp. 174751982093226
Author(s):  
Öznur Şener Cemaloğlu ◽  
Hatice Ogutcu ◽  
Zeliha Hayvalı
Keyword(s):  
Schiff Base ◽  
Crown Ether ◽  
Mass Spectra ◽  
Sodium Perchlorate ◽  
Antimicrobial Activities ◽  
Pathogenic Microorganisms ◽  
Inhibitory Effects ◽  
Antibacterial Effects ◽  
Sodium And Potassium ◽  
C Nmr

New aldehyde- and halogen- (Cl, Br, I) substituted double-armed benzo-15-crown-5 derivatives are synthesized by the reactions of 4′,5′-bis(bromomethyl)benzo-15-crown-5 with 5-chlorosalicylaldehyde, 5-bromosalicylaldehyde, or 5-iodosalicylaldehyde. The sodium and potassium complexes are obtained by reaction of crown ether with sodium perchlorate and potassium iodide, respectively. Novel Schiff base compounds containing three groups of benzo-15-crown-5 are obtained from the condensation of aldehydes with 4′-aminobenzo-15-crown-5. The structures of all compounds are elucidated by elemental analysis, 1H, 13C NMR, IR, and mass spectra. The antifungal and antibacterial effects of the synthesized ligands are evaluated against pathogenic microorganisms and show varying degrees of inhibitory effects against the growth of different pathogenic strains. Graphical abstract

scholarly journals A New Isocoumarin from Cajanus cajan (Fabaceae)

2014 ◽  
Vol 9 (4) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Virginia F. Rodrigues ◽  
Rodrigo R. Oliveira ◽  
Maria Raquel G. Vega
Keyword(s):  
Spectral Data ◽  
Cajanus Cajan ◽  
Mass Spectra ◽  
2D Nmr ◽  
C Nmr

A new isocoumarin, 3-phenyl-8-hydroxy-6-methoxy-5-γ, γ-dimethylallyl-isocoumarin, named cajavilmina (1) and eight known compounds: α-amirenone (2), β-amirenone (3), lupenone (4), 5-hydroxy-7-methoxydihydroflavone (5), longistilin C (6), 3-hydroxy-5-methoxystilbene (7), β-sitosterol (8) and stigmasterol (9) were identified in a dichloromethane fraction from Cajanus cajan leaves. Structures were elucidated by analysis of spectral data, mainly those afforded by 1H, NOEDIFF and 13C NMR (1D and 2D NMR HMQC, HMBC and COSY) and mass spectra.

scholarly journals Neue Selen-Stickstoff-Verbindungen tert-Butyl-seleninylamin, ButNSeO, und Di(tert-butyl)selendiimid, Se(NBut)2/New Selenium-Nitrogen Compounds tert-Butyl-seleninylamine, ButNSeO, and Di(tert-butyl)selenium Diimide, Se(NBut)2

1986 ◽  
Vol 41 (2) ◽  
pp. 144-148 ◽  
Author(s):  
Max Herberhold ◽  
Wolfgang Jellen
Keyword(s):  
Ambient Temperature ◽  
Mass Spectra ◽  
Nitrogen Compounds ◽  
Tert Butyl ◽  
Tert Butylamine ◽  
New Compounds ◽  
C Nmr

The first seleninylamine, tBuNSeO, was prepared from tert-butylamine, tBuNH2, and SeOCl2 (3:1). The selenium diimide Se(NBut)2 was isolated from the corresponding reaction of tBuNH2 and SeCl4 (6:1); it decomposes at ambient temperature to give cyclic Se3(NBut)2. The new compounds were characterized on the basis of their IR , 1H and 13C NMR and mass spectra.

Untersuchungen zur Ringkontraktion am 1,4-Dithia-2,6-diaza-3,5-diborinan-System/ Studies on Ring Contraction of the l,4-Dithia-2,6-diaza-3,5-diborinane System

1988 ◽  
Vol 43 (8) ◽  
pp. 959-962 ◽  
Author(s):  
Carl Habben ◽  
Anton Meiler ◽  
Stefan Pusch
Keyword(s):  
Mass Spectra ◽  
Ring System ◽  
Membered Ring ◽  
Ring Contraction ◽  
C Nmr

AbstractThe 1,4-dithia-2,6-diaza-3,5-diborinanes 1a-d react with elemental sodium with formation of the 1,3-diaza-2,4-diboretidines 2a-d. By use of more sodium in case of 1 d or 3,5-bis(diethylamino)- 2-cyclohexyl-6-trimethylsilyldiborinane, the 1,3-thiaza-2,4-diboretidines 3 were formed. 3.5-Dimethyl-2,6-bis(trimethylsilyl)-1,4-dithia-2,6-diaza-3,5-diborinane gives the borazine 4, The reaction of di-t-butyl-sulfurdiimide with 2,6-di-t-butyl-3,5-dimethyl-1,4-dithia-2,6-diaza-3,5-diborinane leads by ring contraction to the four-membered ring system 5. 1H, 11B, 13C NMR and mass spectra are reported and discussed.

4-N-Benzazolylamino Derivatives of 3-Y-3-Buten-2-one

1992 ◽  
Vol 57 (3) ◽  
pp. 531-539 ◽  
Author(s):  
Viktor Milata ◽  
Dušan Ilavský ◽  
Igor Goljer ◽  
Ján Leško
Keyword(s):  
Nucleophilic Substitution ◽  
Mass Spectra ◽  
Spectral Measurements ◽  
Mild Conditions ◽  
Derivatives Of ◽  
C Nmr

Ethoxymethylene derivatives of 2,4-pentanedione (Ia), 3-oxobutanenitrile (Ib), methyl (Ic) or ethyl (Id) 3-oxobutanoate give with 4- or 5-aminobenzimidazole or benzotriazole, respectively, under mild conditions products of nucleophilic substitution II-V. Structure of these compounds was discussed on the basis of their spectral measurements - IR, UV, 1H, 13C NMR and mass spectra.

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