Synthesis,Characterization, and Biological Properties of Five Enkephalin-like Pentapeptides Containing p-Nitrophenylalanine

Five pentapeptides with the amino acid sequence L -tyrosyl-D -alanyl-glycyl-L -p-nitrophenylalanyl-X, wherein X = L -leucine, L -leucine amide, L -methionine amide, L -1-adamantylalanine amide, and L -neopentylglycine amide were prepared by chemical synthesis in solution and characterized chemically and physically. The effect of the incorporation of the unnatural amino acids adamantylalanine and neopentylglycine, ‘fat’-analogues of leucine and methionine, on the inhibition of electrically evoked contractions of the myenteric plexus-longitudinal muscle preparation from guinea pig ileum was studied. Their activities relative to the peptides with X = Leu · OH, Leu-NH₂, and Met-NH₂ (X = Neo-NH₂ is particularly potent) are discussed in terms of hydrophobic and steric factors, and resistance towards enzymic degradation.     

Synthesis and Biological Activity Test of Some New Five Membered Heterocycles

A new series of 1,3,4‐oxadiazoles, 1,2,4‐triazoles, 1,3,4‐thiadiazoles were synthesized using alkylhydrazides as the starting materials, and then 1,2,4‐triazoles were used to synthesize [1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles. All the compounds were evaluated for in vitro antibacterial activity and antitumor activity.     

Synthesis,Opiate Receptor Binding and Analgesic Activity of Enkephalin Analogues

The synthesis and biological testing of analogues of Met-enkephalin, a recently discovered opioid peptide from mammalian brain, are described. Testing involved determination of affinity constants for an opiate receptor site and of analgesic potency in the tail-flick test in mouse. The effects on opioid activity of modifying various parts of the enkephalin molecule are discussed. Tyr-D -Ala-Gly-MePheMet (O)-ol

1 The ending -ol added to the symbol of an amino acid designates the aminoalcohol obtained by reduction of the α-carboxyl group of the amino acid.

(FK 33-824), which was highly active in these tests, was subsequently selected for clinical testing. The use of two complementary models - in vitro binding studies and in vivo test for analgesia - for the assessment of biological activity in the evaluation of analogues is explained.     

4-氨基喹唑啉类衍生物的合成及体外抗肿瘤活性

2-氨基-4,5-二甲氧基苯甲酸为起始原料,经环化、氯化和取代反应,合成了5个4-氨基喹唑啉类化合物3a~3e,其结构经¹H NMR和MS测试技术进行了表征。采用MTT法测试了化合物3a~3e对人乳腺癌细胞（MCF-7）、人肺癌细胞（A549）和人前列腺癌细胞（PC-3）的体外抗肿瘤活性。结果表明：3b、3d和3e对3种细胞株的活性有一定的抑制作用,并且对A549表现出了一定程度的选择性。通过分子对接模拟研究AMD和3b与 DNA序列d(CGATCG) 之间的相互作用。      

6-氯-4-哌嗪基喹唑啉缩氨基硫脲类化合物的合成及体外抗肿瘤活性

以5-氯-2-氨基苯甲酸和甲酰胺为起始原料,经环化、氯化、取代和缩合反应,合成了3个未见文献报道的含哌嗪的喹唑啉衍生物5a~5c。 其结构用1H NMR、13C NMR、ESI-MS及IR测试技术进行了表征。 采用MTT法测试了化合物5a~5c对人胃癌SGC-7901、人口腔表皮样癌KB和人纤维肉瘤HT-1080的体外抗肿瘤活性。 结果表明,化合物5a~5c对人胃癌SGC-7901和人纤维肉瘤HT-1080有弱的抑制活性,而对人口腔表皮样癌KB无明显抑制活性。     

Synthesis of Multi-O4-phospho-L-tyrosine-Containing Peptides

Multi-O⁴-phospho-L -tyrosine-containing peptides can be synthesized by the global as well as the buildingblock approach. Thus, we prepared by both strategies the triphosphorylated and the three regioisomeric diphosphorylated insulin-receptor-(1142–1153)-dodecapeptide derivatives 7 and 4–6 , respectively, of the parent Thr-Arg-Asp-Ile-Tyr-Glu-Thr-Asp-Tyr-Tyr-Arg-Lys ( 3 ). These phosphorylated peptides are valuable tools to study the regioselectivity of dephosphorylation by phosphatases.     

Synthesis of 4(3H)-Quinazolinone Derivatives and Their in vitro Antitumor Activity

Classical antifolates containing L-glutamic acid moiety in molecule have shortcomings such as drug resistance which is originated from the defective cell transport by mutation, and toxicity to the host which is due to unnecessarily long retention inside normal cells.[1] One strategy to overcome these shortcomings is to design nonclassical lipophilic inhibitors of folate requiring enzymes by deleting or modifying L-glutamic acid component from the folate analogues.     

Synthesis and Antibacterial Activity of Some New 4(3H)Quinazolin-4-one Derivatives

2-Phenylamino-6,8-dibromo-4H-3,1-benzoxazinone has been reacted with nitrogen nucleophiles, such as hydrazine hydrate, amines, and formamide, yielding 4(3H)quinazolinone derivatives; and with sulfur nucleophiles producing the corresponding thioesters. The behavior of aminoquinazolinone and 4(3H)quinazolinone towards some carbon electrophiles under different conditions has been studied.     

Synthesis and in vitro Antimicrobial Activity of Nalidixic Acid Hydrazones

A series of nalidixic acid‐based hydrazones have been synthesized and evaluated for their in vitro antimicrobial activity using the broth microdilution method against a panel of reference strains of microorganisms, including Gram‐positive bacteria, Gram‐negative bacteria, and fungi belonging to yeasts Candida spp. and molds Aspergillus spp., Penicillium spp., and Rhizopus spp. Nalidixic acid derivatives were obtained by condensation reaction of nalidixic acid hydrazide with substituted (hetero)aromatic aldehydes. All compounds have been characterized by ¹H NMR and ¹³C NMR spectra. The antimicrobial activity indicated that compound with indole substituent could be a promising lead for future development of active antifungal agents.     

Synthesis and Antibacterial Activity of New Diaryldiamines

Several new quinolines and quinazolines ( 4, 10, 13 ) have been synthesized from cheap and readily available chemicals through a series of simple chemical transformations. Most of the synthesized compounds have been evaluated for antibacterial activity against Gram positive and Gram negative strains. Some of the synthesized compounds displayed interesting activity but not very promising for further development.     

新型N-甲氧基-N-苯基氨基甲酸酯类化合物的合成及生物活性研究

为了寻找高效、低毒的新农药,采用活性结构拼接法合成了含1H-1,2,4-三氮唑基的N-甲氧基-N-{2-[1-取代苯基-2-(1H-1,2,4-三氮唑-1-基)-1-丙酮]}苯基氨基甲酸甲酯化合物10个。所有的化合物都经^1H NMR、红外、LC／MS进行了表征。生测活性表明,部分化合物对小麦赤霉病、稻瘟病、黄瓜灰霉病、小麦白粉病有较好的抑菌活性。     

Synthesis and Biological Activity of New Aminophosphabetaines

Russian Journal of General Chemistry - Aminophosphabetaines, i.e., isobutyl {[alkyl(dimethyl)ammonio]methyl}phosphonates with higher alkyl substituents at the nitrogen atom, were obtained by a...     

Synthesis and Antimicrobial Activity of Some New 4H-Pyrrolo[1,2-a]benzimidazoles

Some new 4H-pyrrolo[1,2-a]benzimidazoles（2a-2f） have been synthesized. The structures of these compounds were confirmed by IR, tH NMR, mass spectroscopy and elemental analysis. Compound 2a was further confirmed by X-ray diffraction. The in vitro antimicrobial activities of these compounds were determined against some gram-positive bacteria, gram-negative bacteria and fungi and their drug-resistant isolates in comparison with standard drugs. Antimicrobial results indicate that compounds 2c, 2d and 2e show moderately active antibacterial properties, their minimum inhibitory concentrations are from 12.5 μg/mL to 125 μg/mL. In the series, the most active compound against C. albicans is compound 2fwith an MIC value of 31.25 μg/mL.     

Synthesis and In vitro Study of Cytotoxic Activity of New Tetrazole-Containing 2,4-Diamino-1,3,5-triazine Derivatives

Russian Journal of General Chemistry - New tetrazole-containing derivatives of 2,4-diamino-1,3,5-triazine were synthesized. The cytotoxic activity of the obtained compounds against Huh-7 and HeLa...     

Synthesis and Biological Properties of Enkephalin-like Peptides Containing Adamantylalanine in Position 4 and 5

The syntheses of seven [D -ala-²]-enkephalin analogues, H-Tyr-ala-Gly-X-Y, with X-Y = Phe-Ada-OH, Phe-ada-OH, Phe-Ada-NH₂, Phe-ada-NH₂, Ada-Leu-OH, Ada-Leu-NH₂, and Ada-Ada-NH₂ are described. The compounds with Y = Ada (= L -Ada) or ada (= D -Ada) show pronounced morphine-like activities in certain bioassays, whereas those with X = Ada were most inactive. The analogues were used to explore the influence of steric, electronic, and hydrophobic properties of the side chains of X and Y on opioid activity (see [14]).     

4-(N-取代苯基)氨基喹唑啉类化合物的合成及抗磷酸化活性研究

以4-氯喹唑啉为起始原料, 经环化、氯化、取代三步反应, 合成了8个新的4-取代苯基氨基喹唑啉类化合物. 采用¹H NMR, ¹³C NMR, MS, IR及元素分析对目标化合物的结构进行了表征. 生物活性测试表明, 化合物1f在1 μmol• L^－1 浓度下对PC3细胞增殖抑制活性达到88.6%, 进一步研究表明该化合物具有较高的抑制细胞外信号调节激酶(ERK)磷酸化的活性.     

苯并吡喃-4-硫脲类化合物的合成及其血管舒张活性

根据苯并吡喃类钾通道开放剂的作用机理和构效关系,合成了4个新的苯并吡喃-4-硫脲类化合物(3a~3d),其结构经1HNMR,IR,MS和元素分析确证。大鼠体外血管扩张实验结果表明,3(1.0×10-5mol·L-1)对30mmol·L-1KCl诱导的大鼠主动脉条收缩均具有一定程度的抑制作用,其中3a的血管收缩抑制活性较强。