Synthesis, antimicrobial evaluation and in silico studies of the (E)-3-(aryl)-5-styryl-1,2,4-oxadiazoles

In recent years, investigations in the field of oxadiazoles have been intensified due to their numerous therapeutic uses. Oxadiazoles are a class of compounds that exhibit several biological applications, citing antimicrobial, anti-inflammatory, anti-diabetic, anthelmintic, anti-tumor, among others. Encouraged by the biological potential of oxadiazoles, were carried out synthesis, antimicrobial evaluation and in silica studies of five (E)-3-(aryl)-5-styryl-1,2,4-oxadiazoles. In this way, (Z)-aryl-N'-hydroxybenzimidamides and ethyl (E)-cinnamate were synthesized, which were subjected to an O-acylamidoxime reaction after by dehydration using microwave irradiation to form the oxadiazole nucleus. The compounds were characterized by spectroscopic techniques, while in vitro antimicrobial activity was evaluated against S. aureus, E. faecalis, E. coli, P. aeruginosa, and against the fungus C. utilis using the microplate microdilution method. Thus, (Z)-aryl-N'-hydroxybenzimidamides, ethyl (E)-cinnamate, and (E)-3-(aryl)-5-styryl-1,2,4-oxadiazoles were synthesized with yields ranging from moderate to good. The (E)-3-(aryl)-5-styryl-1,2,4-oxadiazoles exhibited a reduced spectrum of action, which were active against the bacterium P. aeruginosa and for the fungus C. utilis.

Synthesis, spectral analysis and pharmacological study of N'- substituted-2-(5-((2,4-dimethylphenoxy)methyl)-1,3,4-oxadiazol-2-ylthio)acetohydrazides

ABSTRACT A series of molecules bearing multiple functional groups were synthesized to study their antibiotic effect against Gram-positive and Gram-negative bacteria and lipoxygenase activity as well. 2,4-Dimethylcarbolic acid (1) was refluxed with ethyl 2-bromoacetate to synthesize ethyl 2-(2,4-dimethylphenoxy)acetate (2). Compound 2 was converted to the corresponding hydrazide 3, again on refluxing with hydrazine. The compound 5-((2,4-dimethylphenoxy)methyl)-1,3,4-oxadiazol-2-thiol (4) was synthesized by the reaction of 3 and CS2 in the presence of KOH. Compound 4 was further converted to the corresponding ester 5 and then 2-(5-((2,4-dimethylphenoxy)methyl)-1,3,4-oxadiazol-2-ylthio)acetohydrazide (6). The final molecules N'-substituted-2-(5-((2,4-dimethylphenoxy)methyl)-1,3,4-oxadiazol-2-ylthio)acetohydrazide, 8a-m, bearing ether, 1,3,4-oxadiazole, thioether, hydrazone and azomethine functional groups were synthesized by stirring the aryl carboxaldehydes 7a-m with 6 in methanol at room temperature. The depicted structures of all synthesized molecules were corroborated by IR, 1H-NMR and EIMS spectral data analysis. 8m and 8i showed substantial antibacterial activity and lipoxygenase inhibitory activity, respectively.

Seguridad y eficacia de ataluren en pacientes con diagnóstico de distrofia muscular de duchenne portadores de una mutación sin sentido en el gen de distrofina / Safety and efficacy of ataluren in patients diagnosed with duchenne muscular dystrophy who carry a nonsense mutation in the dystrophin gene

INTRODUCCIÓN: Antecedentes: El Instituto de Evaluación de Tecnologías en Salud e Investigación ha recibido la solicitud de evaluar el uso de Ataluren para su uso en Pacientes ambulantes mayores de 5 años con diagnóstico de distrofia muscular de Duchenne debida a una mutación sin sentido en el gen de la distrofina dentro del sistema de EsSalud, indicación actualmente no contemplada en el petitorio de medicamentos. Esta acción sigue lo estipulado en la Directiva N° 002-IETSI-ESSALUD-2015 y el objetivo final es determinar el estado del arte sobre la eficacia y seguridad de ataluren. Tecnología Sanitaria de Interés: Ataluren: La PTC124 (3-(5-(2-fluorofeni)-1, 2,4-oxadiazol-3-y1)-ácido benzoico), también conocida como Ataluren (TranslarnaTM) es una molécula pequeña de oxadiazol cuyo mecanismo de acción consiste en cominuar la traducción de ARNm sobre los codones de terminación prematuros causados por la mutación sin sentido, permitiendo la síntesis de distrofina completa y funcional. METODOLOGIA: Estrategia de Busqueda: Se realizó una búsqueda de la literatura con respecto a la eficacia y seguridad de Ataluren para el tratamiento de la DMD en las bases de datos de MEDLINE, EMBASE, CENTRAL, DARE y TRIPDATABASE. Se hizo una búsqueda adicional en www.clinicaltrials.gov, para poder identificar ensayos clínicos aún en elaboración o que no hayan sido publicados. Adicionalmente, se hizo una búsqueda dentro de la información generada por las principales instituciones internacionales oncológicas y agencias de tecnologías sanitarias que realizan revisiones sistemáticas (RS), evaluación de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC). RESULTADOS:Sinopses de la Evidencia: Se realizó la búsqueda bibliográfica y de evidencia científica que sustente el uso de ataluren en DMD según la pregunta PICO establecida. Para el presente documento se seleccionó el siguiente cuerpo de evidencia que es resumido a continuación: Guías Clínicas: Se identificó una única guía práctica realizada en Colombia que hizo mención a este tratamiento. Evaluaciones de tecnología sanitaria: Se identificó una ETS del Reino Unido. Revisiones sistemáticas: No se identificaron revisiones sistemáticas. Estudios de calidad de vida: No se identificaron estudios que evaluaran calidad de vida. Ensayos clínicos: Se identificaron dos ECAs correspondientes a las fases 2a y fase 2 b. Ensayos clínicos en curso: se identificó el registro correspondiente a un estudio de fase III pendiente de publicar sus resultados. CONCLUSIONES: se evidencia que ataluren es un medicamento aún en estudio que no ha demostrado al momento ser diferente a placebo en el tratamiento de la DMD con mutación sin sentido. De hecho, la evidencia disponible que el ataluren no es mejor que el placebo en mejorar indicadores clínicos importantes en el manejo de esta enfermedad, como la DC6M, considerada como desenlace principal en enfermedades raras con compromiso neuromuscular. Ataluren tampoco mostró ser diferente al placebo en mejorar la calidad de vida de los pacientes, ni disminuye los tiempos para realizar tareas motoras como subir o bajar escalones, correr o caminar 10 metros y levantarse desde la posición supina. El Instituto de Evaluación de Tecnología en Salud e investigación ­ IETSI, no aprueba el uso de ataluren para el tratamiento de la DMD con mutación sin sentido del gen de la distrofina.

Synthesis of some novel enzyme inhibitors and antibacterial agents derived from 5-(1-(4-tosyl)piperidin-4-yl)-1, 3, 4-oxadiazol-2-thiol

ABSTRACT Keeping in mind the pharmacological importance of the 1,3,4-oxadiazole moiety, a series of new S-substituted derivatives, 5a-h, of 5-(1-(4-tosyl)piperidin-4-yl)-1,3,4-oxadiazol-2-thiol (3) were synthesized. The reaction of p-toluenesulfonyl chloride (a) and ethyl isonipecotate (b) produced ethyl 1-(4-tosyl)piperidin-4-carboxylate (1) which was further transformed into 1-(4-tosyl)piperidin-4-carbohydrazide (2) by hydrazine hydrate in methanol. Compound 2 was refluxed with CS2 in the presence of KOH to synthesize 5-(1-(4-tosyl)piperidin-4-yl)-1,3,4-oxadiazol-2-thiol (3). The desired compounds, 5a-h, were synthesized by stirring 3 with aralkyl halides, 4a-h, in DMF using NaH as an activator. The structures of synthesized compounds were elucidated by 1H-NMR, IR and EI-MS spectral studies. These compounds were further evaluated for enzyme inhibitory activity against lipoxygenase and alpha-glucosidase, along with antibacterial activity against Gram-negative and Gram-positive bacteria.

RESUMO Tendo em vista a importância farmacológica da porção 1,3,4-oxadiazol, sintetizou-se uma série de novos derivados S-substituídos, 5a-h, de 5-(1-(4-tosi)piperidin-4-il)-1,3,4-oxadiazol-2-tiol (3). A reação do cloreto de p-toluenossulfonila (a), com isonipecotato de (b) etila forneceu 1-(4-tosil)piperidin-4-carboxilato de metila (1), que foi, em seguida, transformado em 1-(4-tosil)piperidin-4-carbo-hidrazida (2) por reação com hidrato de hidrazina em metanol. O composto 2 foi submetido a refluxo com CS2 na presença de KOH para se obter 5-(1-(4-tosil)piperidin-4-il)-1,3,4-oxadiazol-2-tiol (3). Os compostos desejados, 5a-h, foram obtidos por agitação de 3 com haletos de aralquila, 4a-h, em DMF, na presença de NaH. As estruturas dos compostos sintetizados foram elucidadas através de análise dos espectros de 1H-MNR, IR e EI-MS. Estes compostos foram, ainda, avaliados quanto à inibição das enzimas lipoxigenase e alfa-glucosidase, juntamente com a atividade antibacteriana contra bactérias Gram positivas e Gram negativas.

Novel hybrids of (phenylsulfonyl)furoxan and N-benzyl matrinol as anti-hepatocellular carcinoma agents / 药学学报

N-Benzyl matrinol was obtained by hydrolysis, benzylation and reduction reaction from matrine. A series of hybrids (8a-8n) from (phenylsulfonyl)furoxan and N-benzyl matrinol were synthesized and biologically evaluated as anti-hepatocellular carcinoma agents. All target compounds were evaluated for anti-proliferative activity against human hepatocellular Bel-7402, SMMC-7721, Bel-7404, and HepG2 cells in vitro by MTT method. The results indicated that all of these compounds had potent anti-proliferative activity which were more potent than their parent compound and 5-FU, especially 8a-8h and 8j showed the strongest anti-HCC HepG2 cell activity with IC50 values of 0.12-0.93 μmol x L(-1).

Acute stress-induced antinociception is cGMP-dependent but heme oxygenase-independent

Endogenous carbon monoxide (CO), which is produced by the enzyme heme oxygenase (HO), participates as a neuromodulator in physiological processes such as thermoregulation and nociception by stimulating the formation of 3′,5′-cyclic guanosine monophosphate (cGMP). In particular, the acute physical restraint-induced fever of rats can be blocked by inhibiting the enzyme HO. A previous study reported that the HO-CO-cGMP pathway plays a key phasic antinociceptive role in modulating noninflammatory acute pain. Thus, this study evaluated the involvement of the HO-CO-cGMP pathway in antinociception induced by acute stress in male Wistar rats (250-300 g; n=8/group) using the analgesia index (AI) in the tail flick test. The results showed that antinociception induced by acute stress was not dependent on the HO-CO-cGMP pathway, as neither treatment with the HO inhibitor ZnDBPG nor heme-lysinate altered the AI. However, antinociception was dependent on cGMP activity because pretreatment with the guanylate cyclase inhibitor 1H-[1,2,4] oxadiazolo [4,3-a] quinoxaline-1-one (ODQ) blocked the increase in the AI induced by acute stress.

Synthesis, antitumor activity and SAR of C-3 oxadiazole sulfanylacetylhydrazone-substituted fluoroquinolone analogues / 药学学报

To explore an efficient strategy for the conversion of antibacterial fluoroquinolones into antitumor fluoroquinolones, an azole heterocyclic ring of oxadiazole instead of the C-3 carboxylic acid group with a functionalized hydrazone group as a modified side-chain, fifteen novel 2-(fluoroquinolon-3-yl)-oxadiazole-5- sulfanylacetylhydrazone derivatives 7a-7o were designed and synthesized on the basis of the pharmacophore hybridization principle from pefloxacin, separately. The structures for fifteen title compounds were characterized by elemental analysis, 1H NMR and MS, and their in vitro antitumor activity against Hep-3B cell line was evaluated by a MTT assay. The results showed that the title compounds exhibited more significantly inhibitory activity than that of the parent pefloxacin, in which compounds with electron-withdrawing group attached on aryl ring had more potency than that of compounds with electron donating group, especially compounds with a carboxylic substituent were comparable to comparison doxorubicin. It suggests that it is favorable for an improvement of antitumor activity to remain a carboxylic acid unit at the aromatic ring.

Synthesis, characterization and biological screening of N-substituted derivatives of 5-benzyl-1,3,4-oxadiazole-2yl-2''-sulfanyl acetamide

A series of new N-substituted derivatives of 5-benzyl-1, 3, 4-oxadiazole-2yl-2''-sulfanyl acetamide [6a-n] were synthesized in three phases. The first phase involved the sequentially converting phenyl acetic acid into ester, hydrazide and finally cyclized in the presence of CS[2] to afford 5-benzyl-1, 3, 4-oxadiazole-2-thiol. In the second phase N-substituted-2-bromoacetamides were prepared by reacting substituted amines with bromoacetyl bromide in basic media. In the third phase, 5-benzyl-1,3,4-oxadiazole-2-thiol was stirred with N-substituted-2-bromoacetamides in the presence of N,N-dimethyl formamide [DMF] and sodium hydride [NaH] to get the target compounds. Spectral techniques were used to confirm the structures of synthesized compounds. Synthesized compounds were screened against butyrylcho linesterase [BChE], acetylcholinesterase [AChE], and lipoxygenase enzymes [LOX] and were found to be relatively more active against acetylcholinesterase

Synthesis, characterization and anti-inflammatory activity of some 1, 3,4 -oxadiazole derivatives

A series of five-membered heterocyclic rings were synthesized by the reaction between benzoyl chloride and various chlolro-nitro-benzoyl chlorides and semi carbazide to form [C[1]-C[7]] compounds and was tested for their anti-inflammatory activity determined by rat-paw-oedema method. All the synthesis compounds have been characterized by [1]HNMR, IR and Mass spectral data. The compounds were purified by column chromatography. All synthesized derivatives were determined by the carrageenan-induced rat-paw-oedema model for anti-inflammatory activity. The entire compound gives good response for the anti-inflammatory activity: [3-Chloro-N-[5-[3-Chloro-phenyl]-[1,3,4] oxadiazole-2yl] benzamide [C[4]], and [4-Nitro-N-[5-[4-Nitro-phenyl]-[1,3,4] oxadiazole-2yl] benzamide [C[7]]. For this activity, indometacin was used as a standard drug and compared to new synthesized drugs. Some new synthesized drugs have shown better activities for the anti-inflammation

3, 4- dinitro-furazan-based oxidation furazan acute and subchronic toxicity studies / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the 3, 4- dinitro-furazan-based oxidation furazan (DNTF) of sub-acute toxicity and chronic toxicity, to determine the acute toxicity classification DNTF, the nature of toxic effects and major target organ for the development provide the basis for occupational exposure limits.</p><p><b>METHODS</b>( 1) Acute toxicity: The oral gavage method once infected, symptoms of poisoning of animals observed to calculate the LD50DNTF and 95% confidence limits. ( 2) sub-chronic experiment: selection of 96 healthy SD rats were randomly divided into four groups, doses of 25, 56.2, 125 mg/kg and the negative control group, Exposure for ninety days,five days a week, once a day, The rats were killed at end of Exposure, heart, liver, spleen, lung, kidney, brain,testis, uterus were taken to observe the pathological changes.</p><p><b>RESULTS</b>( 1) Acute oral toxicity test results indicate that DNTF rat oral LD50 greater than 5000 mg/kg, DNTF mice treated by oral LD50 4589 mg/kg, 95%confidence limit for the 4026-5230 mg/kg, Acute toxicity grade level is low toxicity compounds. (2) Sub-chronic toxicity experiment, the high-dose male rats, high, medium and low-dose group female rats weight gain than the negative control group, compared with the control group, the difference was statistically significant (P<0.05).125 mg/kg of serum alanine aminotransferase, aspartate aminotransferase was significantly higher. 125 mg/kg dose groups, liver, kidney, lung, testicular factor was significantly higher. Liver, kidney, lung histological examination showed obvious morphological changes.</p><p><b>CONCLUSION</b>Acute toxicity grade DNTF low toxicity level compounds, target organ toxicity of liver, kidney and lung.</p>

Participation of the NO/cGMP/K+ATP pathway in the antinociception induced by Walker tumor bearing in rats

Implantation of Walker 256 tumor decreases acute systemic inflammation in rats. Inflammatory hyperalgesia is one of the most important events of acute inflammation. The L-arginine/NO/cGMP/K+ATP pathway has been proposed as the mechanism of peripheral antinociception mediated by several drugs and physical exercise. The objective of this study was to investigate a possible involvement of the NO/cGMP/K+ATP pathway in antinociception induced in Walker 256 tumor-bearing male Wistar rats (180-220 g). The groups consisted of 5-6 animals. Mechanical inflammatory hypernociception was evaluated using an electronic version of the von Frey test. Walker tumor (4th and 7th day post-implantation) reduced prostaglandin E2- (PGE2, 400 ng/paw; 50 µL; intraplantar injection) and carrageenan-induced hypernociception (500 µg/paw; 100 µL; intraplantar injection). Walker tumor-induced analgesia was reversed (99.3% for carrageenan and 77.2% for PGE2) by a selective inhibitor of nitric oxide synthase (L-NAME; 90 mg/kg, ip) and L-arginine (200 mg/kg, ip), which prevented (80% for carrageenan and 65% for PGE2) the effect of L-NAME. Treatment with the soluble guanylyl cyclase inhibitor ODQ (100% for carrageenan and 95% for PGE2; 8 µg/paw) and the ATP-sensitive K+ channel (KATP) blocker glibenclamide (87.5% for carrageenan and 100% for PGE2; 160 µg/paw) reversed the antinociceptive effect of tumor bearing in a statistically significant manner (P < 0.05). The present study confirmed an intrinsic peripheral antinociceptive effect of Walker tumor bearing in rats. This antinociceptive effect seemed to be mediated by activation of the NO/cGMP pathway followed by the opening of KATP channels.

Part IV: Design, synthesis and antitumor activity of fluoroquinolone C-3 heterocycles: bis-oxadiazole methylsulfide derivatives derived from ciprofloxacin / 药学学报

To explore an efficient strategy for further development of anticancer fluoroquinolone candidates derived from ciprofloxacin, a heterocyclic ring as the bioisosteric replacement of C3 carboxyl group led to a key intermediate, oxadiazole thiol (5), which was further modified to the bis-oxadiazole methylsulfides (7a-7h) and the corresponding dimethylpiperazinium iodides (8a-8h), respectively. Structures were characterized by elemental analysis and spectra data, and their anticancer activities in vitro against CHO, HL60 and L1210 cancer cells were also evaluated by MTT assay. The preliminary results show that piperazinium compounds (8) possess more potent activity than that of corresponding free bases (7).

Cinnamyl alcohol attenuates vasoconstriction by activation of K+ channels via NO-cGMP-protein kinase G pathway and inhibition of Rho-kinase

Cinnamyl alcohol (CAL) is known as an antipyretic, and a recent study showed its vasodilatory activity without explaining the mechanism. Here we demonstrate the vasodilatory effect and the mechanism of action of CAL in rat thoracic aorta. The change of tension in aortic strips treated with CAL was measured in an organ bath system. In addition, vascular strips or human umbilical vein endothelial cells (HUVECs) were used for biochemical experiments such as Western blot and nitrite and cyclic guanosine monophosphate (cGMP) measurements. CAL attenuated the vasoconstriction of phenylephrine (PE, 1 microM)-precontracted aortic strips in an endothelium-dependent manner. CAL-induced vasorelaxation was inhibited by pretreatment with NG-nitro-L-arginine methyl ester (L-NAME; 10(-4) M), methylene blue (MB; 10(-5) M) and 1 H-[1,2,4]-oxadiazolole-[4,3-a] quinoxalin-10one, (ODQ; 10(-6) or 10(-7) M) in the endothelium-intact aortic strips. Atrial natriuretic peptide (ANP; 10(-8) or 10(-9) M) did not affect the vasodilatory effect of CAL. The phosphorylation of endothelial nitric oxide synthase (eNOS) and generation of nitric oxide (NO) were stimulated by CAL treatment in HUVECs and inhibited by treatment with L-NAME. In addition, cGMP and PKG1 activation in aortic strips treated with CAL were also significantly inhibited by L-NAME. Furthermore, CAL relaxed Rho-kinase activator calpeptin-precontracted aortic strips, and the vasodilatory effect of CAL was inhibited by the ATP-sensitive K+ channel inhibitor glibenclamide (Gli; 10(-5) M) and the voltage-dependent K+ channel inhibitor 4-aminopyridine (4-AP; 2 x 10(-4) M). These results suggest that CAL induces vasorelaxation by activating K+ channels via the NO-cGMP-PKG pathway and the inhibition of Rho-kinase.

Dual Inhibition of PI3K/Akt/mTOR Pathway and Role of Autophagy in Non-Small Cell Lung Cancer Cells / 결핵및호흡기질환

BACKGROUND: The phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling axis has emerged as a novel target for cancer therapy. Agents that inhibit this pathway are currently under development for lung cancer treatment. In the present study, we have tested whether dual inhibition of PI3K/Akt/mTOR signaling can lead to enahnced antitumor effects. We have also examined the role of autophagy during this process. METHODS: We analyzed the combination effect of the mTOR inhibitor, temsirolimus, and the Akt inhibitor, GSK690693, on the survival of NCI-H460 and A549 non-small cell lung cancer cells. Cell proliferation was determined by MTT assay and apoptosis induction was evaluated by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Autophagy induction was also evaluated by acridine orange staining. Changes of apoptosis or autophagy-related proteins were evaluated by western blot analysis. RESULTS: Combination treatment with temsirolimus and GSK690693 caused synergistically increased cell death in NCI-H460 and A549 cells. This was attributable to increased induction of apoptosis. Caspase 3 activation and poly(ADP-ribose) polymerase cleavage accompanied these findings. Autophagy also increased and inhibition of autophagy resulted in increased cell death, suggesting its cytoprotective role during this process. CONCLUSION: Taken together, our results suggest that the combination of temsirolimus and GSK690693 could be a novel strategy for lung cancer therapy. Inhibition of autophagy could also be a promising method of enhancing the combination effect of these drugs.

Synthesis and antituberculostic activity of some novel 1,3,4-oxadiazole

A series of 5-[3'-oxo-6'-[substituted aryl]-2',3',4',5'-tetrahydropyridazin-2'-yl methyl]-2-substituted 1,3,4-oxadiazole has been synthesized. Appropriate aromatic hydrocarbon reacts with succinic anhydride in presence of AlCl[3] to yield beta-Aroyl propionic acid [1a]. The corresponding acid is cyclised with hydrazine hydrate to give 6-[substituted aryl]-2,3,4,5-tetrahydro3-pyridazinone [1b]. This intermediate after reaction with ethyl bromo acetate, hydrazinolysed into 3-oxo-6-[substituted aryl]-2,3,4,5-tetrahydropyridazinyl acetohydrazide [1c]. The resulting product was converted into 5-[3'oxo-6'-[substituted aryl]-2',3',4',5'-tetrahydropyridazin-2'-yl methyl]-2-substituted 1,3,4-oxadiazole [Scheme-I]. All the final compounds have been structurally elucidates on the basis of IR, [1]H-NMR, mass spectral data and elemental analysis and screened for antitubercular activity

Inhibitory effect of Suaeda asparagoides (Miq.) extract on the motility of rat gastric antrum is mediated by beta-adrenoceptor / 한국실험동물학회지

Suaeda asparagoides (Miq.) has long been used as a Korean folk herbal medicine for the treatment of functional gastrointestinal disorders. However, reports on its pharmacological activity on gastrointestinal motility are scarce. The present study investigated the effects of Suaeda asparagoides water fraction of the extract (SAWF) on antral motility in vitro. Muscle strips from rat gastric antrum were set up in an organ bath in a circular orientation. SAWF (100 microg/mL) inhibited the spontaneous contraction of antral circular muscle strips. These inhibitory effects were not significantly affected by tetrodotoxin (1 microM), N omega-Nitro-L-arginine methyl ester hydrochloride (100 microM), 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one (10 microM), ryanodine (10 microM) and phentolamine (10 microM). SAWF-induced inhibition was mostly restored by cyclopiazonic acid (10 microM). Furthermore, the beta-adrenergic receptor antagonist, propranolol (10 microM), abolished SAWF-induced inhibition. These results suggest that SAWF may exert its activity on gastrointestinal smooth muscle via a-adrenergic receptors and sarcoplasmic reticulum Ca2+ ATPase.

Part II: Design, synthesis and antitumor action of C3/C3 bisfluoroquinolones linked-cross 2, 5-1, 3, 4oxadiazole / 药学学报

To develop a new small molecular probe for discovering an antitumor lead compound from the replacement of carboxylic group of two molecular antibacterial fluoroquinolones with a heterocyclic ring, a series of the C3/C3 bis-fluoroquinolones tethered with an 1, 3, 4-oxadiazole ring were synthesized as their respective HCl salts, and their structures were characterized by elemental analysis and spectral data. The in vitro antitumor activity against L1210, CHO and HL60 cell lines was also evaluated via the respective IC50 values by methylthiazole trazolium (MTT) assay.

Inhibition of Hypoxic Pulmonary Vasoconstriction of Rats by Carbon Monoxide

Hypoxic pulmonary vasoconstriction (HPV), a unique response of pulmonary circulation, is critical to prevent hypoxemia under local hypoventilation. Hypoxic inhibition of K+ channel is known as an important O2-sensing mechanism in HPV. Carbon monoxide (CO) is suggested as a positive regulator of Ca2+-activated K+ channel (BK(Ca)), a stimulator of guanylate cyclase, and an O2-mimetic agent in heme moiety-dependent O2 sensing mechanisms. Here we compared the effects of CO on the HPV (Po2, 3%) in isolated pulmonary artery (HPV(PA)) and in blood-perfused/ventilated lungs (HPV(lung)) of rats. A pretreatment with CO (3%) abolished the HPV(PA) in a reversible manner. The inhibition of HPV(PA) was completely reversed by 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ), a guanylate cyclase inhibitor. In contrast, the HPV(lung) was only partly decreased by CO. Moreover, the partial inhibition of HPV(lung) by CO was affected neither by the pretreatment with ODQ nor by NO synthase inhibitor (L-NAME). The CO-induced inhibitions of HPV(PA) and HPV(lung) were commonly unaffected by tetraethylammonium (TEA, 2 mM), a blocker of BK(Ca). As a whole, CO inhibits HPV(PA) via activating guanylate cyclase. The inconsistent effects of ODQ on HPV(PA) and HPV(lung) suggest that ODQ may lose its sGC inhibitory action when applied to the blood-containing perfusate.

Effect of environment temperature on the recovery of microdialysis probe for monoamine neurotransmitter / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of environment temperature on the recovery of microdialysis probe for neurotransmitters.</p><p><b>METHODS</b>Neurotransmitters NE, DA, and 5-HT were dialyzed with 4 mm membrane length microdialysis probes in different environmental temperature. There were three conditions: lower temperature condition, the temperature of standard solution and that of the perfusate were both 24 degree; higher temperature condition,both were 37.5 degree; and the middle temperature:the perfusate was 24 degree and the standard solution was 37.5 degree. The concentrations of neurotransmitters in the dialyzed solution and the standard solution were analyzed by HPLC-ECD, and recoveries were then calculated.</p><p><b>RESULT</b>In lower temperature condition,the recoveries of microdialysis probe for NE, DA, 5-HT were 18.3 %, 19.6% and 16.9%, respectively. In middle temperature condition, the recoveries were 29.6%, 30.7% and 24.3%, respectively, and in higher temperature condition, those were 49.2%, 47.5% and 37.2%, respectively. With the analysis of variance, the recoveries for NE, DA, 5-HT increased with temperature significantly (P<0.01).</p><p><b>CONCLUSION</b>Both the perfusate and the standard solution affects the environmental temperature of microdialysis probe, which in turns affects the recovery of microdialysis probe for neurotransmitters. So in order to calculate the recovery more accurately, the standard solution/the perfusate should be kept in body temperature.</p>

Synthesis and antibacterial activity of 3-(4-amino-5-methyl-s-triazol-3-sulfanyl)-1-phenyl-propan-1-one O-(5-substituted phenyl-1,3,4 oxadiazol-2-methyl)-oximes / 药学学报

<p><b>AIM</b>To study the synthetic method and antibacterial activity of amino-heterocyclic compounds coupled oxime-ether group.</p><p><b>METHODS</b>The treatment of 4-amino-3-methyl-5-mercapto-s-triazole (3) with beta-chlorophenyl-propanone to form amino-s-triazole sulfanylphenyl-propanone (4) sequentially followed by oximation with hydroxyl-amine to produce the oximes (5) and etherification with various oxadiazole chloromethanes (6a - j) to yield the title compounds (1a - j). The in vitro antibacterial activities of all newly synthesized compounds were tested against Gram positive bacteria and Gram negative bacteria with the standard 2-fold agar dilution method.</p><p><b>RESULTS</b>Twelve new compounds including two intermediates were synthesized and their structures were confirmed by IR, 1H NMR, MS and elemental analyses. The ten title compounds exhibited the potential antibacterial activities in vitro.</p><p><b>CONCLUSION</b>Theses compounds should be optimized.</p>