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101.
Marcos A. P. Martins Pablo Machado Luciana A. Piovesan Alex F. C. Flores Marli M. A. de Campos Carolina Scheidt Helio G. Bonacorso Nilo Zanatta 《Monatshefte für Chemie / Chemical Monthly》2008,139(8):985-990
A series of twelve 5-trihalomethyl-3-arylisoxazoles was synthesized and screened for antibacterial and antifungal activities.
The compounds were synthesized from the cyclondensation of 1,1,1-trihalo-4-alkoxy-3-alken-2-ones [CX
3C(O)C(R
2)=C(R
1)OR, where X = Cl and F; R=Me; R
2=H; R
1=H, Me, F, Cl, Br, and NO2] with hydroxylamine hydrochloride through a rapid one-pot reaction via microwave irradiation. Some of the 5-trihalomethyl-3-arylisoxazoles exhibited good in vitro anti-Cryptococcus activity.
Correspondence: Marcos A. P. Martins, Núcleo de Química de Heterociclos (NUQUIMHE), Centro de Ciências Naturais e Exatas,
Departamento de Química, Universidade Federal de Santa Maria, 97.105-900 Santa Maria, RS, Brazil. 相似文献
102.
Dayse N. Moreira Clarissa P. Frizzo Kelvis Longhi Nilo Zanatta Helio G. Bonacorso Marcos A. P. Martins 《Monatshefte für Chemie / Chemical Monthly》2008,139(9):1049-1054
The synthesis of eleven 1-cyanoacetyl-5-hydroxy-5-halomethyl-4,5-dihydro-1H-pyrazoles from the reaction of 4-alkoxy-3-alken-2-ones f(R
3C(O)C(R
2) = C(R
1)OR, where R
3 = CF3, CCl3, CHCl2, CO2
Et; R
2/R
1 = H/H, H/Me, H/Et, -(CH2)4-, Me/H, H/Pr, and R = Me, Et) with cyanoacetohydrazide is reported. The reaction was carried out in the ionic liquid ([bmim][BF4]) and molecular solvents. The results showed that when the ionic liquid was used as reaction medium, the reaction time was
drastically decreased and the yield was improved.
Correspondence: Marcos A. P. Martins, Núcleo de Química de Heterociclos – NUQUIMHE, Universidade Federal de Santa Maria, Santa
Maria, RS, Brazil. 相似文献
103.
Synthesis of 1‐Arylethyl‐2‐arylethylamino‐5‐trifluoroacetyl‐1,2,3,4‐tetrahydropyridines and Related Compounds with Potential Cell Efflux Pump Inhibition 下载免费PDF全文
Nilo Zanatta Marcio M. Lobo Josiane M. dos Santos Laura de A. Souza Valquiria P. de Andrade Helio G. Bonacorso Marcos A. P. Martins 《Journal of heterocyclic chemistry》2015,52(6):1776-1781
This study reports a simple, fast, and efficient method for the synthesis of a new series of 1‐arylethyl‐2‐arylethylamino‐5‐trifluoroacetyl‐1,2,3,4‐tetrahydropyridines and related compounds from the reaction of 2‐alkoxy‐5‐trifluoroacetyl‐3,4‐dihydro‐2H‐pyrans with 2‐arylethanamines and related 2‐ethanamines. The desired tetrahydropyridines were obtained in excellent yields (90–98%), through a reaction that can be described as an AAB′ three‐component reaction protocol following an ANRORC‐type mechanism. 相似文献
104.
Marcos A. P. Martins Rogrio A. Freitag Adriano Da Rosa Alex F. C. Flores Nilo Zanatta Helio G. Bonacorso 《Journal of heterocyclic chemistry》1999,36(1):217-220
A one-pot synthesis of 1-methyl- and 1-phenylpyrazole-3(5)-ethyl esters 2,3a-e by the cyclocondensation of β-alkoxyvinyl trichloromethyl ketones 1a-e with methyl and phenyl hydrazine hydrochloride under mild conditions, is reported. A study using compounds 1a-e with different substituents proved that these are versatile building blocks for the synthesis of pyrazole derivatives, having a 3(5)-ethoxycarbonyl substituent in good yields (60–89%). The hydrazine and β-alkoxyvinyl trichloromethyl ketone substituent effects on the reaction regiochemistry on the formation of the 1,3- and 1,5-isomer were observed. 相似文献
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