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1.
Sci Rep ; 13(1): 16501, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37779154

RESUMO

Trityl chloride (TrCl) was efficiently used as a neutral catalyst for the multicomponent cyclization reaction of an aldehyde with dimedone and 6-amino-1,3-dimethyluracil for the preparation of pyrimido[4,5-b] quinolines in chloroform under reflux condition.

2.
RSC Adv ; 13(16): 10642-10649, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37025670

RESUMO

A nano TiO2/porous carbon nanocomposite (TiO2/PCN) was designed by the pyrolysis of peanut shells as bio waste with nano titanium dioxide. In the presented nanocomposite, titanium dioxide is properly placed in the positions and pores of the porous carbon, so that it acts as an optimal catalyst in the nanocomposite structure. The structure of TiO2/PCN was studied by various analyses such as Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray Spectroscopy (EDX), scanning electron microscopy (SEM), SEM coupled EDX (SEM mapping), transmission electron microscopy (TEM), X-ray fluorescence (XRF) and BET. TiO2/PCN was successfully tested as a nano catalyst for the preparation of some 4H-pyrimido[2,1-b]benzimidazoles in high yields (90-97%) and short reaction times (45-80 min).

3.
ACS Omega ; 7(49): 45314-45324, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36530277

RESUMO

DABCO was used as a basic and inexpensive catalyst for the synthesis of some new benzyloxy pyrimido[4,5-b]quinoline derivatives and 1,2,3- triazole-fused pyrimido[4,5-b]quinolines by the one-pot multi-component reaction of various benzyloxy benzaldehydes or benzylic -1,2,3-triazol-4-yl-methoxy benzaldehydes with dimedone and 6-amino-1,3-dimethyluracil at 90 °C under the solvent-free condition.

5.
RSC Adv ; 12(9): 5386-5394, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35425540

RESUMO

Nano-[Fe3O4@SiO2/N-propyl-1-(thiophen-2-yl)ethanimine][ZnCl2] as a nano magnetite Schiff base complex was designed and fully characterized by various analyses such as Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), differential thermal gravimetric analysis (DTA), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), and transmission electron micrographs (TEM). The presented nano magnetite Schiff base complex was used as a heterogeneous catalyst for the synthesis of pyrimido[4,5-b]quinolones by the reaction of aryl aldehyde, dimedone and 6-amino-1,3-dimethyluracil in EtOH : H2O (7 : 3) as a solvent at 60 °C.

6.
RSC Adv ; 11(37): 22751-22755, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35480427

RESUMO

Water was magnetized via an external magnetic field and employed, for the first time, as a solvent in green preparation of 3,4-dihydropyrimidin-2(1H)-ones by the one-pot three-component condensation reaction using boric acid as a catalyst. Shorter reaction times, higher yields, and cleaner reaction profiles were some advantages of using magnetic water.

8.
J Org Chem ; 83(7): 3645-3650, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29504403

RESUMO

1,3-Disulfonic acid imidazolium nitrate {[Dsim]NO3} was prepared and characterized as a new ionic liquid and nitrating agent for the ipso-nitration of various arylboronic acids and nitro-Hunsdiecker reaction of different α,ß-unsaturated acids and benzoic acid derivatives, by in situ generation of NO2 to give various nitroarenes and nitroolefins without using any cocatalysts and solvents under mild conditions.

9.
Ann Med Surg (Lond) ; 15: 22-25, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28217303

RESUMO

BACKGROUND: Medical errors such as retained foreign bodies (RFB) during surgery are not well studied. To define risk factors associated with this type of error, we performed retrospective study. METHODS: We reviewed medical records for unintentional foreign object remaining in the body during surgery such as gender, age, surgery ward, and incident reports referred to several forensic medicine administrations as well as adverse effects of retained foreign bodies and methods for detection of them over a 3-years period from January 2008 through May 2011. RESULTS: Thirty eight patients were involved in the study to have retained foreign bodies (73% sponges and 27% other instruments including 7 (18.42%) cases of other bandages, 2 cases (5.26%) of scissor and 1 case (2.63%) of forceps). The general surgery ward was most commonly involved (47%) followed by the gynecology surgery ward (34%). Men (58%) were more involved with RFB than women (42%). CONCLUSION: Considering the most frequent type of retained foreign bodies and also more frequent involved surgery wards besides detection methods for RFB, a mixed of preventing protocols such as regular counting of devices, post-operative X-ray with radiopaque markers and exact evaluation of surgery site should be employed to reduce the occurrence of retained foreign bodies and its complications.

10.
J Org Chem ; 77(7): 3640-5, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22409592

RESUMO

3-Methyl-1-sulfonic acid imidazolium nitrate ([Msim]NO(3)) as a new Brønsted acidic ionic liquid and nitrating agent was prepared and used for the efficient nitration of aromatic compounds (even aniline derivatives). The dramatic effect of this reagent by in situ generation of nitrogen dioxide as a radical on aromatic compounds to give nitroarenes has been studied.

11.
Malar J ; 1: 2, 2002 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-12057020

RESUMO

BACKGROUND: Rapid diagnosis and correct treatment of cases are the main objectives of control programs in malaria-endemic areas. METHODS AND RESULTS: To evaluate these criteria and in a comparative study, blood specimens were collected from 120 volunteers seeking care at the Malaria Health Center in Chahbahar district. One hundred and seven out of 120 Giemsa-stained slides were positive for malaria parasites by microscopy. Eighty-four (70%) and 20 (16.7%) were identified as having only Plasmodium vivax and Plasmodium falciparum infections, respectively, while only 3 (2.5%) were interpreted as having mixed P. vivax-P. falciparum infections. The target DNA sequence of the 18S small sub-unit ribosomal RNA (ssrRNA) gene was amplified by Polymerase Chain Reaction (PCR) and used for the diagnosis of malaria in south-eastern Iran. One hundred twenty blood samples were submitted and the results were compared to those of routine microscopy. The sensitivity of PCR for detection of P. vivax and P. falciparum malaria was higher than that of microscopy: nested PCR detected 31 more mixed infections than microscopy and parasite positive reactions in 9 out of the 13 microscopically negative samples. The results also confirmed the presence of P. vivax and P. falciparum. CONCLUSIONS: These results suggest that, in places where transmission of both P. vivax and P. falciparum occurs, nested PCR detection of malaria parasites can be a very useful complement to microscopical diagnosis.


Assuntos
Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Parasitemia/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Reação em Cadeia da Polimerase , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Comorbidade , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Parasitemia/parasitologia , Plasmodium falciparum/genética , Plasmodium vivax/genética , Ribotipagem , Especificidade da Espécie
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