N-(顺式-4-异丙基环己基-1-甲酰基)-D-苯丙氨酸和N-(反式-4-异丙基环己基-1-甲酰基)-L-苯丙氨酸的合成

目的合成N-(顺式-4-异丙基环己基-1-甲酰基)-D-苯丙氨酸和N-(反式-4-异丙基环己基-1-甲酰基)-L-苯丙氨酸.方法以(4-异丙基)环己基甲酸为原料,在二环己基碳二亚胺(DCC)作用下,与N-羟基琥珀酰亚胺反应得到(4-异丙基)环己基甲酸琥珀酰亚胺酯(3),柱色谱分离化合物3得到顺式和反式异构体.顺式体与D-苯丙氨酸甲酯发生酰化反应,碱水解后即得到N-(顺式-4-异丙基环己基-1-甲酰)-D-苯丙氨酸;而反式体与L-苯丙氨酸甲酯发生酰化反应,水解后得到N-(反式-4-异丙基环己基-1-甲酰)-L-苯丙氨酸.结果与讨论成功合成了目标化合物,反应总收率分别为39%和31%.     

N-（三氘代甲氧羰基）-L-缬氨酸的合成*

N-(三氘代甲氧羰基)-L-缬氨酸(1)是氘代达卡他韦的关键中间体。以N-叔丁氧羰基-L-缬氨酸(3)为起始物料,4步合成目标产物(1),总收率58%(以氘代甲醇计,收率26%)。以L-缬氨酸甲酯(5’)为起始物料,2步合成化合物(1),总收率68%(以氘代甲醇计,收率30%)。该路线成本降低了约40%,同时大大降低了对环境的污染,适合工业化生产。     

N(2)-L-丙氨酰-L-谷氨酰胺合成路线图解

本文综述了L-丙氨酰-L-谷氨酰胺的合成方法,并给出其合成路线图解。     

N(2)-L-丙氨酰-L-谷氨酰胺及有关物质的高效液相色谱分析

目的考察不同色谱条件下N(2)-L-丙氨酰-L-谷氨酰胺(L-Ala-L-Gln)及其有关物质的色谱行为,建立L-Ala-L-Gln有关物质的高效液相色谱含量测定方法。方法氨基键合硅胶柱(4.6 mm×250 mm,5μm);以乙腈-0.05mol/L磷酸二氢钾缓冲液(用磷酸调pH值至4)70:30为流动相;流速为1.0 mL/min;检测波长为215 nm;柱温为40℃。结果L-Ala-L-Gln在10~100μg/mL浓度范围内呈良好线性关系(r=0.999 8),并且可以同时测定含量和有关物质,重复性试验RSD为0.81%(n=6)。结论此法简单,分离度良好,结果准确,可以用于L-Ala-L-Gln的含量和有关物质的检测。     

柱前衍生化HPLC法测定N(2)-L-丙氨酰-L-谷氨酰胺注射液的含量

目的建立柱前衍生化高效液相色谱(HPLC)法测定N(2)-L-丙氨酰-L-谷氨酰胺注射液含量的方法。方法采用异硫氰酸苯酯作柱前衍生剂,色谱柱为Waters sunfire ODS柱(4.6 mm×250 mm),流动相为:乙腈-0.1 mol/L醋酸钠(用稀醋酸调整pH 5.50)为44∶56,柱温30℃,检测波长254 nm。结果线性范围为0.025~2.5mg/mL(r=0.999 8),平均加样回收率为99.9%,RSD为0.5%。结论此法操作简单快速,灵敏度高,结果准确可靠,适用于N(2)-L-丙氨酰-L-谷氨酰胺注射液中N(2)-L-丙氨酰-L-谷氨酰胺的含量测定。     

N-（三氘代甲氧羰基）-L-缬氨酸的合成*

N-（ 三氘代甲氧羰基)-L-缬氨酸（1）是氘代达卡他韦的关键中间体。以N-叔丁氧羰基-L-缬氨酸（3）为起始物料,4步合成目标产物（1）,总收率58%（以氘代甲醇计,收率26%）。以L-缬氨酸甲酯（5’）为起始物料,2步合成化合物（1）,总收率68%（以氘代甲醇计,收率30%）。该路线成本降低了约40%,同时大大降低了对环境的污染,适合工业化生产。     

N-叔丁氧羰基-O-苄基-L-苏氨醇的制备及其在合成奥曲肽中的应用研究

目的：合成N-叔丁氧羰基-O-苄基-L-苏氨醇（化合物1）,并将其作为原料合成多肽药物奥曲肽。方法：以侧链羟基和氨基均被保护的苏氨酸为原料,分别采用混合酸酐法、四氢锂铝（LiAlH4）法以及卡特缩合剂（BOP）法进行还原反应,柱层析分离纯化,合成目标化合物,经红外光谱（IR）、核磁共振氢谱（1H-NMR）及质谱（MS）进行表征。合成的目标化合物经脱除氨基保护,用于奥曲肽合成。结果：混合酸酐法、LiAlH4法、BOP法合成目标化合物1的收率分别为83.2%、73.4%、69.5%,纯度分别为99.0%、98.8%、98.5%,并经过结构表征确证;奥曲肽合成收率为6%,纯度〉98%。结论：混合酸酐法合成化合物1的操作简便、收率高、纯度高,并成功应用于奥曲肽的合成。     

N-(2-甲氧羰基苯氧/硫乙酰基)-N-取代甘氨酸的合成

Ｎ－（２－甲氧羰基苯氧／硫乙酰基）－Ｎ－取代甘氨酸的合成江云，龚康孙，蔡纯一，周群，虞文（成都华西医科大学药学院６１００４１）血管紧张素转化酶抑制剂（ＡＣＥＩ）类药物近年来已在治疗高血压和充血性心力衰竭方面起着重要作用［１］，其临床应用及新药寻找等方...     

N-(2-巯基吡啶-3-甲酰)-N-烃基甘氨酸及其双硫化合物的合成

肾素—血管紧张素系统在调节人体血压时有重要作用。当此系统机能亢进时,会引起血压上升。血管紧张素转化酶(ACE)抑制剂既能对该系统有调节作用,又能抑制有降压作用的缓激肽分解,而起到降血压的效应。此外,它对充血性心力衰竭也有良好疗效。新近报道,ACE抑制剂尚有抗心绞痛作用。     

肾素抑制剂研究-N-(α-羟基-β-羟基烃基)三肽酯的合成

设计合成了8个N-(α-羟基-β-羟基烃基)三肽酯作为肾素抑制剂。α-烯酸与NBS和水反应生成赤式的α-溴-β-羟基酸(Ⅱ),Ⅱ与Phe-Val-Tyr(Phe)OC_2H_5·HCl缩合得到的化合物1～8,都具有抑制肾素活性的作用(K_i=0.49～1.70mmol/L),并推证了它们的构型。     

Synthesis and Chemotactic Activity of the fMLP Analog HCO-Hmb-Leu-Phe-OMe

The new fMLP analog HCO-Hmb-Leu-Phe-OMe ( 1 ), containing (S)-2-hydroxy-4-(methylthio)butyric acid (Hmb) in place of L -methionine at the N-terminal position, has been synthesized and fully characterized. The peptide 1 has been designed in order to improve the understanding of the role exerted by the formamido group in the binding interaction with the formylpeptide chemotactic receptors. Chemotaxis, superoxide anion production, and lysozyme release have been measured for both 1 and its deformylated analog Hmb-Leu-Phe-OMe 2 . Results indicate that a strong hydrogen bond of the OH·…O?C type may complement a weak H-bonding interaction involving the formylic proton as H-bond donor.     

Enhancement of N-formyl-methionyl-leucyl-phenylalanine (fMLP) binding to isolated human neutrophils

Short chain aliphatic alcohols have previously been found to enhance fMLP binding to human neutrophils, presumably by non-specific mechanisms involving increased membrane hydrophobicity or decreased microviscosity. We report the discovery of highly potent fMLP binding enhancers with 30,000 times the potency of the alcohols. Activity of the compounds is specific since slight changes in structure drastically alter their ability to enhance binding and since closely related compounds inhibit rather than enhance binding. The effects of experimental compounds on enhancement or inhibition of fMLP binding are paralleled by similar actions on fMLP-stimulated shape change of neutrophils.     

Synthesis and separation of protected tripeptide epimers by RP-HPLC

Twenty three epimeric pairs of protected tripeptides of the type Z-Ala-Xaa-Val-OMe have been synthesized by conventional coupling procedures in solution. Optimal conditions for baseline separation of LLL/LDL epimers were found by high-performance liquid chromatography on a RP-18 column with aqueous methanol as mobile phase. The hydrophobic parameters (log kw) were determined for all tripeptides.     

Cyclic melanotropins. 5. Importance of the C-terminal tripeptide (Lys-Pro-Val)

In previous work we reported that [Cys4,Cys10]-alpha-MSH (II) and Ac-[Cys4,Cys10]-alpha-MSH4-13-NH2 (III) were superpotent melanotropins. Ac-[Cys4,Cys10]-alpha-MSH4-10-NH2 (VI), which constitutes the cyclic analogue of the putative active site sequence -Met4-Glu5-His6-Phe7-Arg8-Trp9-Gly10- of alpha-MSH, was much less active. In the present investigation the contribution of the Lys11 and Pro12 residues of the C-terminal carboxamide tripeptide -Lys11-Pro12-Val13-NH2 to the potency of Cys4,Cys10 containing cyclic melanotropins was studied. Ac-[Cys4,Cys10]-alpha-MSH4-11-NH2 (V) was less potent than alpha-MSH in the frog and lizard skin bioassays and the mouse S-91 (Cloudman) melanoma adenylate cyclase assay but more potent than Ac-[Cys4,Cys10]-alpha-MSH4-10-NH2 in the three assays studied. Ac-[Cys4,Cys10]-alpha-MSH4-12-NH2 (IV) was considerably more potent than the cyclic 4-11 melanotropin and was, in fact, equipotent or even slightly more potent than [Cys4,Cys10]-alpha-MSH and Ac-[Cys4,Cys10]-alpha-MSH4-13-NH2 over the linear portion of the dose-response in all three bioassays. These results demonstrate that Lys11 and Pro12 but to a lesser extent Val13 of the C-terminal tripeptide sequence contributes to the potency of the cyclic melanotropins. The further substitution of a D-Phe7 for the L-Phe7 residue into the cyclic 4-12 analogue resulted in a highly potent compound Ac-[Cys4,D-Phe7,Cys10]-alpha-MSH4-12-NH2 (VII) that exhibited highly prolonged biological activity.     

Synthesis of tritiated tuftsin and macrophage inhibitory tripeptide via acetylenic intermediates

Acetylenic analogues of tuftsin (Thr-Dah-Pro-Arg) and of a macrophage inhibitory tripeptide (Thr-Dah-Pro) have been synthesized by conventional procedures in solution (Dah = 2,6-diamino-4-hexynoic acid). These acetylenic derivatives are intermediates for the preparation of structurally unmodified, tritiated peptides. Catalytic tritiation of Thr-Dah-Pro-Arg and of Thr-Dah-Pro has afforded the radioactive tetra- and tripeptides with specific activities of 11.4 Ci/mmol and 37 Ci/mmol, respectively.     

Effects of non-steroidal anti-inflammatory drugs on isolated human polymorphonuclear leukocytes (PMN): chemotaxis, superoxide production, degranulation and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) receptor binding

1. We have examined the effects of tolmetin and meclofenamate on isolated human PMN functions under FMLP stimulating conditions. 2. In a dose dependent manner, tolmetin and meclofenamate inhibited all PMN functions, except that tolmetin stimulated PMN chemotaxis. 3. Meclofenamate was much more potent than tolmetin as an inhibitory agent. 4. We also conducted competitive receptor binding assays for tolmetin, meclofenamate and ibuprofen on the FMLP receptor. 5. All three NSAID inhibited FMLP binding in a dose dependent manner with the potency order being meclofenamate greater than ibuprofen greater than tolmetin.     

Enzymatic conversion of the unnatural tripeptide delta-(D-alpha-aminoadipyl)-L-cysteinyl-D-valine to beta-lactam antibiotics

Incubation of the unnatural tripeptide delta-(D-alpha-aminoadipyl)-L-cysteinyl-D-valine (DLD-ACV) with a partially purified extract of Cephalosporium acremonium resulted in the production of deacetoxycephalosporin C. The extract contained isopenicillin N synthetase (cyclase) and deacetoxycephalosporin C synthetase (expandase) but no penicillin epimerase activity, and was incubated aerobically in the presence of the components of the cyclase and expandase reaction mixtures (Fe++, ascorbate, dithiothreitol, alpha-ketoglutarate and ATP). The reaction was sensitive to penicillinase, indicating penicillin N to be an intermediate. However, when ring expansion was prevented by omission of alpha-ketoglutarate and ATP, no penicillin N was detected.     

Synthesis and cytogenetic effects of aminoquinone derivatives with a di- and a tripeptide

Quinones are of significant interest due to their important role in specific cellular functions. Quinoproteins are a big class of oxyreductive agents occurring in bacteria and other organisms. In this investigation derivatives of 2-amino-1,4-benzoquinone, 2-amino-1,4-naphthoquinone and 2-amino-5,8-dihydroxy-1,4-naphthoquinone with a di- and a tripeptide were prepared for first time. The effect of the synthesized compounds on sister chomatid exchange (SCE) rates and human lymphocyte proliferation kinetics on a molar basis was studied. Among these coupled products the most effective in inducing SCEs and depressing proliferation rate indices is the coupling product of 2-amino-1,4-naphthoquinone with the tripeptide GHK (10). Next in order of magnitude in inducing cytogenetic effects is 2-amino-1,4-naphthoquinone (2) and its coupling products with glycine and serine (4 and 5), while the rest displayed marginal activity.     

Cyclic ADP-ribose mediates formyl methionyl leucyl phenylalanine (fMLP)-induced intracellular Ca(2+) rise and migration of human neutrophils

Although cyclic ADP-ribose (cADPR), a novel Ca(2+)-mobilizing mediator, is suggested to be involved in the functions of neutrophils in rodents, its role in human neutrophils remains unclear. The present study examined the ability of cADPR to mobilize Ca(2+) and mediate formyl methionyl leucyl phenylalanine (fMLP)-stimulated increase in cytosolic free Ca(2+) concentration ([Ca(2+)](i)) and migration in human neutrophils. cADPR induced Ca(2+) release from digitonin-permeabilized neutrophils, and the release was blocked by 8Br-cADPR, an antagonist of cADPR. Immunophilin ligands, FK506 and rapamycin, but not cyclosporine A, inhibited cADPR-induced Ca(2+) release. 8Br-cADPR partially reduced fMLP-induced [Ca(2+)](i) rise and abolished the rise in combination with 2APB, an IP(3)-receptor antagonist. Anti-CD38Ab and NADase that interfere with cADPR formation, reduced the fMLP-induced [Ca(2+)](i) rise. When beta-NAD(+), a substrate of ADP-ribosyl cyclase, and cADPR were added to the medium, the former gradually increased [Ca(2+)](i) and the latter potentiated the fMLP-induced [Ca(2+)](i) rise. The beta-NAD(+)-induced [Ca(2+)](i) rise in Ca(2+)-free medium was inhibited by anti-CD38Ab, 8Br-cADPR, FK506, ruthenium red, and thapsigargin. mRNAs of nucleoside transporter (NT), ENT1, ENT2, CNT, and CNT3 were expressed in neutrophils; and their inhibitors, inosine, uridine, and s-(4-nitrobenzyl)-6-thioinosine, reduced the [Ca(2+)](i) rise induced by beta-NAD(+) and fMLP. fMLP-timulated migration was inhibited by the removal of Ca(2+) from the medium or by the addition of 8Br-cADPR, anti-CD38Ab, NADase, and NT inhibitors. These results suggest that cADPR was synthesized extracellularly by CD38, transported into the cells through NTs, and then Ca(2+) was mobilized by FK506-binding protein-dependent process. This process may be involved in fMLP-induced intracellular Ca(2+) signaling and migration in human neutrophils.