共查询到20条相似文献,搜索用时 15 毫秒
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Akhter Hossain M Bathgate RA Kong CK Shabanpoor F Zhang S Haugaard-Jönsson LM Rosengren KJ Tregear GW Wade JD 《Chembiochem : a European journal of chemical biology》2008,9(11):1816-1822
Insulin-like peptide 5 (INSL5) was first identified through searches of the expressed sequence tags (EST) databases. Primary sequence analysis showed it to be a prepropeptide that was predicted to be processed in vivo to yield a two-chain sequence (A and B) that contained the insulin-like disulfide cross-links. The high affinity interaction between INSL5 and the receptor RXFP4 (GPCR142) coupled with their apparent coevolution and partially overlapping tissue expression patterns strongly suggest that INSL5 is an endogenous ligand for RXFP4. Given that the primary function of the INSL5-RXFP4 pair remains unknown, an effective means of producing sufficient quantities of this peptide and its analogues is needed to systematically investigate its structural and biological properties. A combination of solid-phase peptide synthesis methods together with regioselective disulfide bond formation were used to obtain INSL5. Both chains were unusually resistant to standard synthesis protocols and required highly optimized conditions for their acquisition. In particular, the use of a strong tertiary amidine, DBU, as N(alpha)-deprotection base was required for the successful assembly of the B chain; this highlights the need to consider incomplete deprotection rather than acylation as a cause of failed synthesis. Following sequential disulfide bond formation and chain combination, the resulting synthetic INSL5, which was obtained in good overall yield, was shown to possess a similar secondary structure to human relaxin-3 (H3 relaxin). The peptide was able to inhibit cAMP activity in SK-N-MC cells that expressed the human RXFP4 receptor with a similar activity to H3 relaxin. In contrast, it had no activity on the human RXFP3 receptor. Synthetic INSL5 demonstrates equivalent activity to the recombinant-derived peptide, and will be an important tool for the determination of its biological function. 相似文献
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以取代苯甲醛为原料,采用醇醛缩合反应和珀金反应完成了反,反-2,4-二甲基-5(对硝基苯基)戊-2,4-二烯酸和反,反-2,4-二甲基-5-(间硝基苯基)戊-2,4-二烯酸的有效全合成,并确定了最佳反应条件,化合物3b为尚未见文献报道的新化合物,其结构经红外光谱,核磁共振证实。 相似文献
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以2,4-二羟基苯甲醛和环戊酮为原料,无水乙醇为溶剂,40%的NaOH水溶液为催化剂,经Claisen-Schmidt反应催化合成了标题化合物,其结构通过1HNMR、MS进行表征。化合物的初步生物活性测试结果表明,该化合物具有很强的酪氨酸酶抑制活性,半抑制浓度(Ic50)为0.78μmol/L,比曲酸(Ic50=28.59μmol/L)的活性强36倍多。抑制动力学研究表明,该化合物对酪氨酸酶的抑制属于竞争性抑制类型。 相似文献
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Six new compounds [(CpTi)X, Cp=upsilon(nabla)-c(nabla)H(nabla), X=Ge, Ga, B) have been prepared and their Keggin structures determined by elementary analysis, IR, UV, (infinity)H NMR and (infinity for all)WNMR spectrometry. The results show that the complexes retain Keggin structure. The complexes exhibit antitumoral activity in vitro as shown by MTT experiment. 相似文献
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合成了二(2-氧代-5,5-二甲基-1,3-二氧杂-2-磷杂环己基)氧化磷,用元素分析、IR、^1HNMR和MS等分析方法表征了它的组成和结构,解释了其谱图现象。 相似文献
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以水合肼为还原剂,用偶合物合成了2-(2'-羟基-5'-甲基苯基)苯并三唑-N-氧化物.考察了原料比,氢氧化钠用量及浓度等因素对产品收率的影响.得到了适宜的反应条件偶合物、水合肼与氢氧化钠的摩尔比为10.535.3,氢氧化钠溶液的浓度为18%,反应温度80~82℃,收率达95%以上,纯度为99%. 相似文献
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为了寻求具有除草活性的化合物,以3-甲基苯酚为起始原料,通过酰化反应及取代反应合成了中间体4-(4,6-二甲氧基嘧啶-2-氧基)-2-甲基苯甲醛(Ⅲ),运用中间体(Ⅲ)通过三组分一锅法合成了12个2-[4-(4,6-二甲氧基嘧啶-2-氧基)-2-甲基苯基]-2-(取代苯胺)乙腈类衍生物,三组分反应具有良好的收率,为64%~96%。所合成化合物的结构经核磁共振氢谱、质谱和元素分析进行了表征。 相似文献
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合成了12新的取代肼基甲酸酯类化合物,其化学结构 经IR,MS,^2HNMR和元素分析确证。生物活性测试结果显示所合成的化合物棉花立枯病菌等均有一定的抑制活性。 相似文献
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