0000000000139795

AUTHOR

M. L. Bajardi

ChemInform Abstract: Mass Spectrometry of 3,4-Dihydroquinazolin-4-ones of Pharmaceutical Interest. Part 3. Electron Ionization Mass Spectra of 2-Substituted-3-( 5′-pyrazolyl)-4(3H)-quinazolinones.

The fragmentation reactions induced by electron impact of eighteen title compounds has been investigated with the aid of low beam energy spectra (14 eV, nom. value), metastable ion detection, high resolution measurements and labelling experiments. The loss of the 4-carbonyl oxygen together with the 3-substituent, which constitutes a characteristic fragmentation route of 3-aryl and 3-heteroaromatic substituted-4(3H)-quinazolinones, is again observed, but the presence of a carboxyethyl group at the 4′-position of the pyrazole ring is responsible of an anomalous loss of 47 daltons from the molecular ion. Lastly, a comparison with the previously described behaviour of 3-(5′-isoxazolyl) derivati…

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Synthesis of New 2-{[(Phenoxy or Phenyl)acetyl]amino}benzoic Acid Derivatives as 3α-Hydroxysteroid Dehydrogenase Inhibitors and Potential Antiinflammatory Agents

A number of 2-([(phenoxy or phenyl)acetyl]amino)benzoic acid derivatives were prepared in about 50% yield from (phenoxy or phenyl)acetyl chloride and anthranilic acid derivatives. All the compounds were tested as in vitro inhibitors of 3 alpha-hydroxysteroid dehydrogenase, since enzyme inhibition predicts potential antiinflammatory activity in vivo. The most active compounds 3 l, m, s are about 3.5 times more active than acetylsalicylic acid (ASA). Activity is influenced by electronic as well as steric effects.

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Synthesis of polycyclic fused benzimidazole derivatives

Am easy method for the synthesis of tetraeyclie systems containing an imidazole and an iso-thiazole or an imidazole and a thiazine ring, by reacting 2H-1,3-benzothiazine-2-thion-4(3H)one with aromatic primary diarnines is reported. The structures were assigned based upon mass spectra and modes of cleavage of the compounds. The most important fragments are described.

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One-step synthesis, crystallographic studies and antimicrobial activity of new 4-diazopyrazole derivatives

Summary A number of new 4-diazopyrazole derivatives were prepared by the reaction of 1- R -3-methyl-5(R 1 -substituted)benzamidopyrazoles with a sevenfold excess of nitrous acid in acetic medium. The compounds were tested for activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus faecalis, Listeria monocytogenes, Candida albicans, Candida tropicalis and Paecilomyces varioti . The highest microbial susceptibility was shown by Gram-positive bacteria, with minimum inhibitory concentrations (MIC) in the range 0.5–12.5 μg/mL. For S aureus the R 1 substituents were screened utilizing the Topliss operational scheme. The 4-nitro g…

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ChemInform Abstract: Synthesis of New 2-(((Phenoxy or Phenyl)acetyl)amino)benzoic Acid Derivatives as 3α-Hydroxysteroid Dehydrogenase Inhibitors and Potential Antiinflammatory Agents.

A number of 2-([(phenoxy or phenyl)acetyl]amino)benzoic acid derivatives were prepared in about 50% yield from (phenoxy or phenyl)acetyl chloride and anthranilic acid derivatives. All the compounds were tested as in vitro inhibitors of 3 alpha-hydroxysteroid dehydrogenase, since enzyme inhibition predicts potential antiinflammatory activity in vivo. The most active compounds 3 l, m, s are about 3.5 times more active than acetylsalicylic acid (ASA). Activity is influenced by electronic as well as steric effects.

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Studies in organic mass spectrometry. IV. Electron impact induced fragmentation of 2-substituted 3-(5-isoxazolyl)-4(3H)-quinazolinones of pharmaceutical interest

The fragmentation under electron impact of thirteen 2-substituted-3-(5-isoxazolyl)-4(3H)-quinazolinones has been investigated with the aid of metastable ion detection and high resolution measurements. Molecular ions are always abundant and the main primary fragmentation route involves acetonitrile elimination through isoxazole ring opening. The other common processes, particularly those leading to the abundant [R-C8H4N2]+ ion (b or b'), as well as those due to the nature of the 2-substituent are reported and discussed.

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ChemInform Abstract: One-Step Synthesis, Crystallographic Studies and Antimicrobial Activity of New 4-Diazopyrazole Derivatives.

Summary A number of new 4-diazopyrazole derivatives were prepared by the reaction of 1- R -3-methyl-5(R 1 -substituted)benzamidopyrazoles with a sevenfold excess of nitrous acid in acetic medium. The compounds were tested for activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus faecalis, Listeria monocytogenes, Candida albicans, Candida tropicalis and Paecilomyces varioti . The highest microbial susceptibility was shown by Gram-positive bacteria, with minimum inhibitory concentrations (MIC) in the range 0.5–12.5 μg/mL. For S aureus the R 1 substituents were screened utilizing the Topliss operational scheme. The 4-nitro g…

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ChemInform Abstract: Researches on Antiinflammatory Agents. Studies on Some New 3-(Pyrazol-5-yl)-1,2,3-benzotriazin-4(3H)-ones and -quinazolin-4(3H)-ones.

Following our research on analgesic and antiinflammatory active compounds containing the pyrazole nucleus, a number of 3-(pyrazol-5-yl)-1,2,3-benzotriazin-4(3H)-ones and quinazolin-4(3H)-ones was synthetized and tested. The results of tests for analgesic, antiexudative and antioedema activities, as well as for induction of lesion in the gastric mucosa, are reported and discussed.

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Studies of the synthesis of heterocyclic compounds. Part VII. The preparation of some new 3- and 5-amino-pyrazoles by endocyclicN-substitution of 3(5)-aminopyrazoles

By reaction of some 4-carbethoxy(or cyano)-3(5)-R-5(3)-aminopyrazoles 1 with 2-nitrobenzoyl chloride or 2-nitrobenzenesulfonyl chloride, a number of novel 3- and 5-amino-1-(2-nitrobenzoyl or 2-nitrobenzene-sulfonyl)pyrazoles 6 and 7 were obtained. Every compound appearing during the endocyclic N-substitution process can be identified and determined by glc. The use of nmr offers a rapid, unambigous method for determining the proposed structures.

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Facile synthesis of 5-benzamido-4-diazopyrazole derivatives, a class of biologically active agents and key intermediates

Abstract By reacting l-R1-3-R2-5-(R3-substituted)benzamidopyrazoles with a great ex-cess of nitrous acid in acetic acid media, the related 4-diazoderivatives in 65–80% yields were obtained.

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ChemInform Abstract: Facile Synthesis of 5-Benzamido-4-diazopyrazole Derivatives, a Class of Biologically Active Agents and Key Intermediates.

Abstract By reacting l-R1-3-R2-5-(R3-substituted)benzamidopyrazoles with a great ex-cess of nitrous acid in acetic acid media, the related 4-diazoderivatives in 65–80% yields were obtained.

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Mass spectrometry of 3,4-dihydroquinazolin-4-ones of pharmaceutical interest. Part3. Electron ionization mass spectra of 2-substituted-3-(5′-pyrazolyl)-4(3H)-quinazolinones

The fragmentation reactions induced by electron impact of eighteen title compounds has been investigated with the aid of low beam energy spectra (14 eV, nom. value), metastable ion detection, high resolution measurements and labelling experiments. The loss of the 4-carbonyl oxygen together with the 3-substituent, which constitutes a characteristic fragmentation route of 3-aryl and 3-heteroaromatic substituted-4(3H)-quinazolinones, is again observed, but the presence of a carboxyethyl group at the 4′-position of the pyrazole ring is responsible of an anomalous loss of 47 daltons from the molecular ion. Lastly, a comparison with the previously described behaviour of 3-(5′-isoxazolyl) derivati…

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