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1.
Cochrane Database Syst Rev ; (11): CD007876, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26585317

RESUMO

BACKGROUND: Many media are commercially available for culturing pre-implantation human embryos in assisted reproductive technology (ART) cycles. It is unknown which culture medium leads to the best success rates after ART. OBJECTIVES: To evaluate the safety and effectiveness of different human pre-implantation embryo culture media in used for in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) cycles. SEARCH METHODS: We searched the Cochrane Menstrual Disorders and Subfertility Group's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the National Research Register, the Medical Research Council's Clinical Trials Register and the NHS Center for Reviews and Dissemination databases from January 1985 to March 2015. We also examined the reference lists of all known primary studies, review articles, citation lists of relevant publications and abstracts of major scientific meetings. SELECTION CRITERIA: We included all randomised controlled trials which randomised women, oocytes or embryos and compared any two commercially available culture media for human pre-implantation embryos in an IVF or ICSI programme. DATA COLLECTION AND ANALYSIS: Two review authors independently selected the studies, assessed their risk of bias and extracted data. We sought additional information from the authors if necessary. We assessed the quality of the evidence using Grades of Recommendation, Assessment, Development and Evaluation (GRADE) methods. The primary review outcome was live birth or ongoing pregnancy. MAIN RESULTS: We included 32 studies in this review. Seventeen studies randomised women (total 3666), three randomised cycles (total 1018) and twelve randomised oocytes (over 15,230). It was not possible to pool any of the data because each study compared different culture media.Only seven studies reported live birth or ongoing pregnancy. Four of these studies found no evidence of a difference between the media compared, for either day three or day five embryo transfer. The data from the fifth study did not appear reliable.Six studies reported clinical pregnancy rate. One of these found a difference between the media compared, suggesting that for cleavage-stage embryo transfer, Quinn's Advantage was associated with higher clinical pregnancy rates than G5 (odds ratio (OR) 1.56; 95% confidence interval (CI) 1.12 to 2.16; 692 women). This study was available only as an abstract and the quality of the evidence was low.With regards to adverse effects, three studies reported multiple pregnancies and six studies reported miscarriage. None of them found any evidence of a difference between the culture media used. None of the studies reported on the health of offspring.Most studies (22/32) failed to report their source of funding and none described their methodology in adequate detail. The overall quality of the evidence was rated as very low for nearly all comparisons, the main limitations being imprecision and poor reporting of study methods. AUTHORS' CONCLUSIONS: An optimal embryo culture medium is important for embryonic development and subsequently the success of IVF or ICSI treatment. There has been much controversy about the most appropriate embryo culture medium. Numerous studies have been performed, but no two studies compared the same culture media and none of them found any evidence of a difference between the culture media used. We conclude that there is insufficient evidence to support or refute the use of any specific culture medium. Properly designed and executed randomised trials are necessary.


Assuntos
Meios de Cultura , Embrião de Mamíferos , Fertilização in vitro , Oócitos , Injeções de Esperma Intracitoplásmicas , Aborto Espontâneo , Meios de Cultura/efeitos adversos , Transferência Embrionária , Feminino , Humanos , Nascido Vivo , Gravidez , Taxa de Gravidez , Gravidez Múltipla , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Molecules ; 20(2): 2835-6, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25671333

RESUMO

The authors wish to revise the Author Affiliation section of the title paper, published in Molecules [1], (doi:10.3390/molecules191219648, website: http://www.mdpi.com/1420-3049/19/12/19648). To recognize the fact that the research described was performed in part at the facilities of Taif University and to acknowledge that institution's generous financial support[...].


Assuntos
Benzopiranos/química , Benzopiranos/síntese química , Micro-Ondas
3.
Molecules ; 20(2): 1842-59, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25625680

RESUMO

Bromination of N-substituted homophthalimides and tetrahydropyrido[4,3-d]- pyrimidine-5,7-diones produces 4,4-dibromohomophthalimide and 8,8-dibromo-tetrahydropyrido[4,3-d]pyrimidine-5,7-dione derivatives, respectively, that can be used as precursors for spiro derivatives. The dibromo derivatives react with different binucleophilic reagents to produce several spiroisoquinoline and spirotetrahydropyrido[4,3-d]- pyrimidine-5,7-dione derivatives, respectively. Reaction of the dibromo derivatives with malononitrile produces dicyanomethylene derivatives which react with different binucleophiles to produce new spiro derivatives. All new compounds are prepared by using the usual chemical conditions and microwave assisted conditions. The latter conditions improved the reaction yields, reduced reaction times and ameliorated the effects on the surrounding environment as the reactions are carried out in closed systems. Structures of the newly synthesized compounds are proved using spectroscopic methods such as IR, MS, 1H-NMR and 13C-NMR and elemental analyses. Some of the newly synthesized compounds were tested for their antimicrobial activities, whereby four of them showed moderate activities and the rest showed low or no activities towards the investigated species.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Pirimidinas/síntese química , Quinolinas/síntese química , Compostos de Espiro/síntese química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/efeitos dos fármacos , Lactococcus lactis/efeitos dos fármacos , Micro-Ondas , Penicillium/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pirimidinas/farmacologia , Quinolinas/farmacologia , Compostos de Espiro/farmacologia
4.
Molecules ; 19(12): 19648-64, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25432014

RESUMO

6-Hydroxy-2-oxo-2H-chromene-4-carbaldehyde (2), 6-chloro-2-oxo-2H-chromene-4-carbaldehyde (3) and 6-hydrazinyl-4-methyl-2H-chromen-2-one (5) were prepared as single-pharmacophore motif key intermediates. Compounds 2, 3 and 5 were incorporated in a series of multicomponent reactions (MCRs), under microwave assistance as well as conventional chemical synthesis processes, to afford a series of three and/or four-pharmacophoric-motif conjugates 8a,b, 11, 13, 16, 17, 19 and 20 in good yields. The newly synthesized compounds were characterized by IR, NMR, 13C-NMR, MS and elemental analyses. Finally the synthesized compounds have been screened for their biological activity whereupon they exhibited remarkable antimicrobial activity on different classes of bacteria and the fungus.


Assuntos
Benzopiranos/síntese química , Benzopiranos/farmacologia , Química Orgânica/métodos , Micro-Ondas , Tiazolidinas/química , Bactérias/efeitos dos fármacos , Benzopiranos/química , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nitrilas/síntese química , Nitrilas/química , Tiazolidinas/síntese química
5.
Artigo em Inglês | MEDLINE | ID: mdl-24290356

RESUMO

Two new dithiolate copper(II) and nickel(II) complexes with the ligand tert-butyl N-(2-mercaptoethyl)-carbamate (Boc-SH) were prepared. Their structures were established to be [(Boc-S)2M], where M=Cu (1) and Ni (2) by using elemental analysis, thermal analysis, molar conductivity, FT-IR, Raman, UV/VIS, and ESR as well as EI-mass spectroscopic methods. The X-ray structure of the ligand Boc-SH was also determined. Spectral data showed that the carbamate ligand act as anioinic bidentate through one immine nitrogen and one thiolate sulfur donor atoms. The spectral techniques suggest that both complexes appear to have square planar geometries. The very low electrical conductance of the two complexes supports their neutral nature. The redox behaviors of the obtained complexes were also investigated by cyclic voltammetry. The monomeric nature of both complexes was assessed from their magnetic susceptibility values. The thermoanalytical data evidence that complex (2) is stable up to 165°C and undergo complete decomposition, resulting in NiO as a residual product. The TEM image of the obtained oxide residue showed its nanosize cluster, suggesting that complex (2) may be used as a precursor for the formation of nanooxide. The methylation reactions of the two dithiolate complexes (1) and (2) with methyl iodide appear to occur intramolecularly at the metal(II)-bound dithiolates, forming the metal(II)-bound dithioether complexes [M(Boc-SCH3)2]I2 with clean second-order constants of 7.95×10(-2) and 10.59×10(-2) M(-1) s(-1), respectively.


Assuntos
Materiais Biomiméticos/química , Carbamatos/química , Complexos de Coordenação/química , Cobre/química , Níquel/química , Compostos de Sulfidrila/química , Alquilação , Biocatálise , Domínio Catalítico , Cristalografia por Raios X , Técnicas Eletroquímicas , Escherichia coli/enzimologia , Proteínas de Escherichia coli/química , Metilação , O(6)-Metilguanina-DNA Metiltransferase/química , Oxirredução , Espectrofotometria Infravermelho , Análise Espectral Raman , Fatores de Transcrição/química
6.
Molecules ; 18(1): 832-44, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23344196

RESUMO

Aiming for the synthesis of new heterocyclic compounds containing a sulfonamido moiety suitable for use as antibacterial agents, the precursor ethyl {[4-N-(4,6-dimethylpyrimidin-2-yl)sulfamoyl]phenylazo}cyanoacetate was reacted with a variety of active methylene compounds producing pyran, pyridine and pyridazine derivatives. Also, the reactivity of the precursor hydrazone towards hydrazine derivatives to give pyrazole and oxazole derivatives was studied. On the other hand, treatment of the same precursor with urea, thiourea and/or guanidine hydrochloride furnished pyrimidine and thiazine derivatives, respectively. The newly synthesized compounds were tested for antibacterial activity, whereby eight compounds were found to have high activities.


Assuntos
Antibacterianos/síntese química , Pirazóis/síntese química , Piridazinas/síntese química , Pirimidinas/síntese química , Sulfonamidas/síntese química , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Ciclização , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Nitrilas , Oxazóis/síntese química , Oxazóis/farmacologia , Proteus mirabilis/efeitos dos fármacos , Pirazóis/farmacologia , Piridazinas/farmacologia , Pirimidinas/farmacologia , Serratia marcescens/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Sulfonamidas/farmacologia
7.
Molecules ; 17(8): 9652-67, 2012 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-22890170

RESUMO

Biginelli reaction of ethyl acetoacetate, thiourea and the appropriate aromatic aldehyde was used to produce ethyl 4-aryl-6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates, that reacted with bromomalononitrile to give ethyl 3-amino-5-aryl-2-cyano-7-methyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylates rather than the isomeric 7H-thiazolo[3,2-a]pyrimidines. Thiazolopyrimidine derivatives reacted with carbon disulphide to yield ethyl 9-aryl-7-methyl-2,4-dithioxo-2,3,4,9-tetrahydro-1H-thiazolo[3,2-a:4,5-d']dipyrimidine-8-carboxylates, that reacted with phenacyl bromide to produce ethyl 8-methyl-10-(4-methoxyphenyl)-3-substituted-5-thioxo-2(un)subatituted-10H-thiazolo[3'',2'':1',2']pyrimido[4',5':4,5]thiazolo[3,2-a]pyrimidine-9-carboxylates. The aforementioned reactions were carried out using both conventional chemical methods and with the assistance of microwave irradaition. Comparison between both methods showed that the microwave assisted method is preferable because of the time reduction and yield improvements achieved. The new compounds were tested for their biological activity as antioxidants, antibacterial or antifungal agents. Some of the new compounds were found to have moderate to good antioxidant and antimicrobial activities.


Assuntos
Anti-Infecciosos/síntese química , Antioxidantes/síntese química , Micro-Ondas , Pirimidinas/síntese química , Pirimidinas/farmacologia , Tiazóis/síntese química , Tiazóis/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pirimidinas/química , Tiazóis/química
8.
Molecules ; 17(6): 6930-43, 2012 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-22728367

RESUMO

Isothiazolopyridines, pyridothiazines and pyridothiazepines are important compounds that possess valuable biological activities. This paper reports on the synthesis of these compounds using both conventional chemical methods and modern microwave techniques. 3-Bromo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide, 5-arylazo-6-hydroxy-4-methyl-2-thioxo-1,2-dihydropyridine-3-carboxamides, 3,5-bis-arylazo-6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-caboxamide, 4-methyl-2,3,6,7-tetra-hydroisothiazolo[5,4-b]-pyridine-3,6-dione, 2,2'-(methylene-bis-(sulfanediyl))bis(4-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide), 2-hydroxy-5-methyl-4H-pyrido[3,2-e][1,3]-thiazine-4,7(8H)-dione and 2-arylmethylene-8-hydroxy-6-methyl-2,3,4,5-tetrahydropyrido-[3,2-f][1,4]thiazepine-3,5-diones have been prepared from 6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide. Some of these compounds were prepared using microwave-assisted reaction conditions, that provided higher yields in shorter times than the conventional methods.


Assuntos
Piridinas/síntese química , Tiazepinas/síntese química , Tiazinas/síntese química , Halogenação , Micro-Ondas , Acoplamento Oxidativo , Piridinas/química , Tiazepinas/química , Tiazinas/química
9.
Molecules ; 16(6): 4937-57, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21677606

RESUMO

Rapid and efficient solvent-free synthesis of 4-amino-3-mercapto-6-[2-(2-thienyl)vinyl]-1,2,4-triazin-5(4H)-one 1 under microwave irradiation is described. Some new fused heterobicyclic nitrogen systems such as 1,2,4-triazino[3,4-b][1,3,4]thiadiazinones, 1,3,4-thiadiazolo[2,3-c][1,2,4]triazinone and pyrazolo[5,1-c]-[1,2,4]triazine-7-carbonitrile, have been synthesized by treatment of 1 with bifunctional oxygen and halogen compounds, CS2/KOH and malononitrile via heterocyclization reactions, in addition to some uncondensed triazines. Structures of the products have been deduced from their elemental analysis and spectral data (IR, ¹H-NMR, ¹³C-NMR). Select new synthesized compounds were screened as anticancer agents, with some showing activity as cytotoxic agents against different cancer cell lines.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Micro-Ondas , Tiofenos/química , Triazinas/síntese química , Triazinas/farmacologia , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células HCT116 , Células Hep G2 , Humanos , Processos Fotoquímicos , Triazinas/química
10.
Molecules ; 16(6): 4549-59, 2011 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-21629183

RESUMO

3-Amino-3-thioxopropanamide (1) reacted with ethyl acetoacetate to form 6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide (2), which reacted with α-haloketones 3 to produce 2,3-disubstituted-8-hydroxy-6-methyl-2H,5H-pyrido[3,2-f]-[1,4]thiazepin-5-ones 4a-c. Benzoylation of 4c led to the formation of the dibenzoate derivative 9. Compounds 4a-c could be prepared stepwise through the formation of S-alkylated derivatives 10a-c. Compounds 2, 4a-c, 9 and 10a-c were prepared using microwave as a source of heat, and gave better yields in shorter times than those achieved by traditional methods. Coupling of 4a-c with arenediazonium chlorides proceeded unusually to give the 6-hydroxy-4-methyl-2-(arylazo)thieno[2,3-b]pyridin-3(2H)-one ring contraction products 14. Structures of the newly synthesized compounds were proven by spectral and chemical methods.


Assuntos
Micro-Ondas , Tiazepinas/química , Tiazepinas/síntese química
11.
Molecules ; 16(3): 1956-72, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21358587

RESUMO

6-[(4-Methoxy/4,9-dimethoxy)-7-methylfurochromen-5-ylideneamino]-2-thioxo-2,3-dihydropyrimidin-4-ones 1a,b were prepared by reaction of 6-amino-2-thiouracil with visnagen or khellin, respectively. Reaction of 1a,b with methyl iodide afforded furochromenylideneaminomethylsulfanylpyrimidin-4-ones 2a,b. Compounds 2a,b were reacted with secondary aliphatic amines to give the corresponding furochromen-ylideneamino-2-substituted pyrimidin-4-ones 3a-d. Reaction of 3a-d with phosphorus oxychloride yielded 6-chlorofurochromenylidenepyrimidinamines 4a-d, which were reacted with secondary amines to afford furochromenylideneamino-2,6-disubstituted pyrimidin-4-ones 5a-d. In addition, reaction of 5a-d with 3-chloropentane-2,4-dione gave 3-chloro-furochromenylpyrimidopyrimidines 6a-d. The latter were reacted with piperazine and morpholine to give 1-(furochromenyl)-pyrimidopyrimidine-3,6,8-triylpiperazines or -3,6,8-triylmorpholines 7a-d. The chemical structures of the newly synthesized compound ware characterized by IR, ¹H-NMR, ¹³C-NMR and mass spectral analysis. These compounds were also screened for their analgesic and anti-inflammatory activities. Some of them, particularly 3-7, exhibited promising activities.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Quelina/análogos & derivados , Quelina/química , Pirimidinas/síntese química , Animais , Espectroscopia de Ressonância Magnética , Pirimidinas/farmacologia , Ratos , Espectrofotometria Infravermelho
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