Mass spectral studies of aromatic aza analogues of juvabione

1986 ◽  
Vol 51 (12) ◽  
pp. 2879-2883
Author(s):  
R. K. Mahajan ◽  
Neelam Gupta ◽  
Satinder K. Uppal
Keyword(s):  
Mass Spectra ◽  
Spectral Studies ◽  
Fragmentation Pattern ◽  
Mass Spectral ◽  
Secondary Amides

Mass spectra of title compounds I-VI have been studied with a view to comparing the fragmentation pattern of secondary amides in different structural environments.

scholarly journals Electron Impact Ionization Mass Spectra of 3-Amino 6-Chloro2-methyl Quinazolin-4-(3H)-one Derivative

2021 ◽  
pp. 1-5
Author(s):  
Osarumwense Peter Osarodion ◽  
◽  
Omotade Treasure Ejodamen ◽  
Keyword(s):  
Electron Impact ◽  
Mass Spectra ◽  
Impact Ionization ◽  
Cyclic Compound ◽  
Electron Impact Ionization ◽  
Ionization Mass ◽  
Fragmentation Pattern ◽  
Molecular Ion ◽  
Mass Spectral ◽  
Characteristic Fragmentation

Looking at the previous studies on quinazolinones derivatives, only limited information’s are available on their mass spectral along with the preparation of novel quinazolin-4-(3H)-one derivatives The condensation of Methyl-2-amino-4-Chlorobenzoate with acetic anhydride yielded the cyclic compound 2-methyl 7-Chloro-1, 3-benzo-oxazine-4-one (1) which further produce 3-Amino-2-Methyl 7-Chloro quinazolin-4(3H)-ones (2) via the reaction with hydrazine hydrate. The compounds synthesized were unequivocally confirmed by means of Infrared, Nuclear Magnetic Resonance (1H and 13C), Gas Chromatography-Mass spectrophotometry and Elemental analysis. Discussion: The molecular ion of m/z 235 fragments to give m/z 220 by loss of –NH group. The ion of m/z 220 was broken to give m/z 206 by losing CH2 group and fragment to m/z 177 by loss of HCO. This fragmented to m/z 162 by loss of –CH3 group and then m/z 136 by loss of CN group. The loss of O gave m/z 120 which fragment to give m/z 93 by loss of –HCN and finally gave m/z 65 by loss of CO group. Conclusion: The electron impact ionization mass spectra of compound 2show a weak molecular ion peak and a base peak of m/z 235resulting from a cleavage fragmentation. Compound 2 give a characteristic fragmentation pattern. From the study of the mass spectra of compound 2, it was found that the molecular ion had fragmented to the m/z 220. The final fragmentation led to ion of m/z 93 and ion of mass m/z 65, respectively

scholarly journals Mass Spectral Fragmentation Pattern of Ν,N′ -Diphenylformamidines

1977 ◽  
Vol 32 (10) ◽  
pp. 1156-1159 ◽  
Author(s):  
Neil G. Keats ◽  
Jean E. Rockley ◽  
Lindsay A. Summers
Keyword(s):  
Mass Spectra ◽  
Molecular Ions ◽  
Fragmentation Pattern ◽  
Mass Spectral Fragmentation ◽  
Mass Spectral ◽  
Hydrogen Migration ◽  
Mass Spectral Fragmentation Pattern

The base peaks in the mass spectra of Ν,N′-diphenylformamidine, N,N′-di-(4-chlorophenyl)formamidine and N,N′-di-(3-chlorophenyl)formamidine are due to the molecular ions of aniline, 4-chloroaniline and 3-chloroaniline respectively. The species responsible for the base peaks are thought to be formed by rupture of the CH-NH bond with concomitant hydrogen migration.

Infrared, N.M.R. and mass spectral studies on 3-Amino-4-aryl-5-aryl(or alkyl)imino-4,5-dihydro-1,2,4-thiadiazoles

1975 ◽  
Vol 28 (3) ◽  
pp. 591 ◽  
Author(s):  
CP Joshua ◽  
KN Rajasekharan
Keyword(s):  
Spectral Data ◽  
Structure Elucidation ◽  
Mass Spectra ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Fragmentation Patterns ◽  
Chemical Evidence

Some 3-amino-4-aryl-5-aryl(or alkyl)imino-4,5-dihydro-1,2,4-thiadiazol, previously prepared and assigned structures on chemical evidence, are now confirmed in structure by a detailed study of their spectra. While i.r, and n.m.r, spectral data confirm the nature of the ring present in these compounds, mass spectra confirm the assignment of substituents on the ring. Mass spectra of these compounds exhibit specific fragmentation patterns and consequently are useful in structure elucidation of substituted 4,5-dihydro-1,2,4-thiadiazoles.

Synthesis of phenethanolamine derivatives with potential β-adrenergic antagonistic activity

1975 ◽  
Vol 28 (5) ◽  
pp. 1023 ◽  
Author(s):  
SJ Pasaribu ◽  
LR Williams
Keyword(s):  
Magnetic Resonance ◽  
Ring Opening ◽  
Proton Magnetic Resonance ◽  
Mass Spectra ◽  
Antagonistic Activity ◽  
Spectral Studies ◽  
Aryl Ring ◽  
Mass Spectral

The mass spectra of bromonitroacetophenones, intermediates in the synthesis of phenethanolamine derivatives containing a nitro and bromo group in the aryl ring, have been studied. The acetophenones were converted into the corresponding α,β-epoxystyrenes, which were then treated with various amines, and proton magnetic resonance and mass spectral studies were used to confirm the direction of ring opening and purity of the products.

scholarly journals Mass Spectral Studies on Some Naturally Occurring Phloroglucinol Derivatives. III. The Mass Spectra of Some Mono- and Bicyclic Phloroglucinol Derivatives from Rhizomes of Different Dryopteris Species.

1972 ◽  
Vol 26 ◽  
pp. 89-101 ◽  
Author(s):  
Mauri Lounasmaa ◽  
Arto Karjalainen ◽  
Carl-Johan Widén ◽  
Aarre Huhtikangas ◽  
W. B. Pearson ◽  
...  
Keyword(s):  
Mass Spectra ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Naturally Occurring ◽  
Phloroglucinol Derivatives

scholarly journals Mass Spectral Studies on Some Naturally Occurring Phloroglucinol Derivatives. Part I. The Mass Spectra of Filicinic Acid and its Acetyl, Propionyl, and Butyryl Derivatives.

1971 ◽  
Vol 25 ◽  
pp. 3428-3440 ◽  
Author(s):  
Mauri Lounasmaa ◽  
Arto Karjalainen ◽  
Carl-Johan Widén ◽  
Aarre Huhtikangas ◽  
J. Koskikallio ◽  
...  
Keyword(s):  
Mass Spectra ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Naturally Occurring ◽  
Phloroglucinol Derivatives

Mass spectral studies of some desaurins and related 3,5-bismethylene-1,2,4-trithiolanes

1968 ◽  
Vol 46 (3) ◽  
pp. 365-375 ◽  
Author(s):  
Peter Yates ◽  
Thomas R. Lynch ◽  
L. S. Weiler
Keyword(s):  
Carbonyl Group ◽  
Mass Spectra ◽  
Molecular Ions ◽  
Spectral Studies ◽  
Mass Measurements ◽  
Metastable Peak ◽  
Fragmentation Pathways ◽  
Mass Spectral ◽  
Accurate Mass Measurements ◽  
Doubly Charged

The mass spectra of three desaurins and four related 3,5-bismethylene-1,2,4-trithiolanes have been interpreted with the aid of metastable peak assignments and accurate mass measurements. Strong molecular ion peaks are observed in the case of the aryl desaurins but not in that of their trithiolane counterparts. A variety of fragmentation pathways are postulated for the molecular ions, including cleavage on either side of a carbonyl group and elimination of a molecule of acylthioketene. In the case of the desaurins the latter process results in the formation of acylthioketene molecular ions, which could be distinguished from the doubly charged desaurin molecular ions. In the case of two of the trithiolanes, it is proposed that the ions resulting from loss of acylthioketene from the molecular ions undergo a novel type of McLafferty rearrangement and loss of carbon suboxysulfide to give aryl mercaptan molecular ions.

Mass spectral studies of lanthanide chelates. II. Lanthanide chelates of three fluorinated β-diketones

1976 ◽  
Vol 29 (8) ◽  
pp. 1845 ◽  
Author(s):  
SE Livingstone ◽  
WA Zimmermann
Keyword(s):  
Mass Spectrometer ◽  
Mass Spectra ◽  
Nitrate Solution ◽  
Alcoholic Solution ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Lanthanide Nitrate ◽  
Aqueous Alcoholic Solution ◽  
Lanthanide Chelates ◽  
Chemical Behaviour

The lanthanide chelates MetL3,nH2O (Met = Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, or Yb; L = PhCO= CHCOCF3, p-MeC6H4CO=CHCOCF3, p-MeOC6H4CO=CHCOCF3; n = 2, 3 or 1) have been isolated. The conditions were found to be critical, involving the slow addition of an ammoniacal aqueous alcoholic solution of the β-diketone to an excess of the lanthanide nitrate solution while the pH was maintained within the range 6.0-6.5. The mass spectra of most of the chelates were obtained and were essentially similar and fluorine migration to the metal was found to occur. Although a peak for the ion M-L (M = MetL3+) is present in the spectra, peaks for M-2L and M-3L are absent; however, peaks were obtained for the ions M-2L+ F and M-3L+2F (Met111F2). A peak for the ion M- L+ F (Met11F) was obtained when Met = Sm, Eu and Yb. The valency change from 3 to 2 occurring in the mass spectrometer in the case of samarium, europium and ytterbium is in accordance with their chemical behaviour in solution.

scholarly journals Mass Spectral Studies on Some Naturally Occurring Phloroglucinol Derivatives. Part II. The Mass Spectra of 6-Methyl-, 6-Ethyl-, 6-Propyl-, and 6-Isopropyl-2,3-dihydropyran-2,4-diones.

1971 ◽  
Vol 25 ◽  
pp. 3441-3450 ◽  
Author(s):  
Mauri Lounasmaa ◽  
Arto Karjalainen ◽  
Carl-Johan Widén ◽  
Aarre Huhtikangas ◽  
J. Koskikallio ◽  
...  
Keyword(s):  
Mass Spectra ◽  
Spectral Studies ◽  
Mass Spectral ◽  
Naturally Occurring ◽  
Phloroglucinol Derivatives
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