2-（5-氨基-1，2，4-噻二唑-3-基）-2-（Z）-甲氧亚氨基乙酸S-苯并噻唑硫酯的合成

2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酰胺与2-巯基苯并噻唑为原料,哌啶为溶剂,在三乙胺催化下反应制得头孢菌素中间体2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酸S-苯并噻唑硫酯,收率约76%。     

口服低分子量非肽类胃素抑制剂阿利克仑的合成研究

本文通过对胃素抑制剂阿利克仑合成的三个重要中间体（2R）-3-甲基-2-（4-甲氧基-3-（3-甲氧丙氧基）苄基）-1-丁醇（中间体1）、（2S,4E）-异丙基-5-氯-4-戊烯酸甲酯（中间体2）、3-氨基-2,2-二甲基丙酰胺（中间体3）的合成路线分别从原料、反应条件、收率等方面对每条路线优劣进行了评价,以求找到最佳的工业化生产合成路线。     

4-氨基-5-氯-2-乙氧基-N-[[4-(4-氟苄基)-2-吗啉基]甲基]苯甲酰胺的合成

目的合成4-氨基-5-氯-2-乙氧基-N-[[4-(4-氟苄基)-2-吗啉基]甲基]苯甲酰胺.方法以中间体4-氨基-5-氯-2-乙氧基苯甲酸和中间体B、C为原料合成目标产物.结果合成目标产物的收率为90·0%,提高近30·0%;中间体4-氨基-5-氯-2-乙氧基苯甲酸、中间体邻苯二甲酰亚胺钾、中间体B和中间体C为鲁南贝特制药有限公司生产确证.结论通过对合成路线的优化,使生产收率提高,降低成本,工艺更适于工业化的生产.     

2-氨基-3-甲基吡啶的制备

2-氨基-3-甲基吡啶(1)是制备多种药物的中间体。文献以2-氰基-3-甲基吡啶为原料、过氧化氢为氧化剂,碱性条件下不完全水解氰基得3-甲基-2-吡啶甲酰胺,再经Hoffman降解得1,总收率74%,此法原料较贵,中间体均须分离纯化,操     

甲磺酸达比加群酯的合成

目的:研究和改进甲磺酸达比加群酯的合成工艺。方法:以4-甲氨基-3-硝基苯甲酸(2)和3-(吡啶-2-基氨基)丙酸乙酯(3)为原料,经酰氯化、酰胺化、中和成盐和还原制得重要中间体3-[[3-氨基-4-(甲氨基)苯甲酰基](吡啶-2-基)氨基]丙酸乙酯(5)。5再与N-(4-氰基苯基)甘氨酸经酰胺化、闭环、中和成盐、成脒、酰化,进而与甲磺酸成盐制得甲磺酸达比加群酯。结果:中间体及目标化合物经质谱、核磁共振谱、红外光谱等确证,整个工艺的总收率为33.9%。结论:本路线操作简便、成本较低、条件温和、步骤少,适合工业化生产。     

PZM21的合成工艺研究

目的 优化μ阿片受体偏向激动剂PZM21的合成工艺.方法 以L-酪氨酰胺为原料,经甲基化、硼烷还原反应得到关键中间体(S)4-[3-氨基-2-(二甲基氨基)丙基]苯酚盐酸盐(I);以噻吩-3-甲醛为原料,经Henry反应、氢化铝锂还原、手性拆分、缩合反应得到关键中间体4-硝基苯基(S)-[1-(噻吩-3-基)丙-2-基...     

2-脱氧链霉胺取代衍生物的结构确证和1H核磁定量

对新型氨基糖苷类抗生素合成中(本文阐述的是阿米卡星合成中的2个中间体,而非新型氨基糖苷类抗生素)的两个重要中间体进行结构确证和核磁定量。采用13C NMR、1H NMR、1H 1H-COSY、HMBC和MS对化合物1和化合物2进行了结构确证,并分别以马来酸和甲酸钠为内标物、D2O为溶剂,通过比较马来酸δ6.23ppm内标峰和化合物1δ5.05ppm、δ5.66ppm定量峰面积,以及甲酸钠δ8.36ppm内标峰和化合物2 δ2.00ppm、δ5.72ppm定量峰面积计算化合物1和化合物2的含量。化合物1为3-氨基-3-脱氧-α-D-葡吡喃糖基-(1→6)-[2,3,4,6-四脱氧-2,6–二氨基-α-D-赤式-己吡喃糖基-(1→4)]-1-N-[(2S)-4-氨基-2-羟基-1-氧丁基]-2-脱氧-D-链霉胺,化合物2为3-氨基-3-脱氧-α-D-葡吡喃糖基-(1→6)-[2,3,4,6-四脱氧-2,6–二氨基-α-D-赤式-3-烯-己吡喃糖基-(1→4)]-1-N-[(2S)-4-氨基-2-羟基-1-氧丁基]-2-脱氧-D-链霉胺,化合物1和化合物2的含量分别为64.98%和75.38%。化合物1和化合物2是2-脱氧链霉胺取代衍生物,采用氢核磁共振内标法可快速、准确地型氨基糖苷类抗生素合成过程中无商品化标准品的重要中间体进行定量分析。     

1-氨基-2-丙醇的拆分

(2S,3S)-(-)-酒石酸于水中拆分消旋1-氨基-2-丙醇,然后用强酸性阳离子树脂分离,得到核苷类药物合成中间体(R)-(-)-1-氨基-2-丙醇,收率66.6%,拆分剂可直接回收利用.     

盐酸依福地平合成工艺改进

目的研究盐酸依福地平的合成工艺。方法以苯胺为原料，经4步反应制得中间体3-氨基-2-丁烯酸-2-（N-苄基N-苯基）-氨基乙酯（5）；以新戊二醇和间硝基苯甲醛为原料，经过4步反应制得中间体3-（5，5-二甲基-2-氧代-2-[1，3，2]二氧杂磷杂环己基）-4-（3-硝基苯基）-丁-3-烯-2-酮（9）；中间体5和9经环合、成盐反应制得盐酸依福地平。结果与结论目标化合物的结构经IR、MS和。H-NMR谱确证。改进后的工艺路线操作简便。总收率达39．5％，适合工业化生产。     

(口恶)拉戈利关键中间体的新合成方法

本研究报道了(口恶)拉戈利关键中间体(R)-[2-[5-(2-氟-3-甲氧基苯基)-3-[2-氟-6-(三氟甲基)苄基]-4-甲基-2,6-二氧代-3,6-二氢嘧啶-1(2H)-基]-1-苯乙基]氨基甲酸叔丁酯(1)的新合成路线.以3-氨基巴豆酸乙酯为原料,经氯甲酸苯酯活化后与(R)-叔丁基(2-氨基-1-苯乙基)氨基...     

Synthesis of a 2'-deoxyguanosine adduct of cis-2-butene-1,4-dial, a reactive metabolite of furan

Furan is a liver and kidney toxicant and a hepatocarcinogen in rodents. Its reactive metabolite, cis-2-butene-1,4-dial, reacts with nucleosides to form adducts in vitro. The reaction with 2'-deoxyguanosine generates 3-(2'-deoxy-beta-D-erythropentafuranosyl)-3,5,6,7-tetrahydro-6-hydroxy-7-(ethane-2"-al)-9H-imidazo[1,2-alpha]purine-9-one as the major reaction product. A synthetic approach to this adduct is presented in this report. The key step in this synthesis is the preparation of 2'-deoxy-3',5'-O-bis(tert-butyldimethylsilyl)-1-(1,2,5,6-tetrahydroxyhexan-3-yl)guanosine. Treatment of this intermediate with sodium periodate gave three reaction products: a one-substituted adduct, 2'-deoxy-3',5'-O-bis(tert-butyldimethylsilyl)-1-(2,5-dihydroxy-tetrahydrofuran-3-yl)guanosine; a 1,N(2)-cyclic adduct, 3-[2'-deoxy-3',5'-O-bis(tert-butyldimethylsilyl)-beta-D-erythropentafuranosyl]-6-hydroxy-8-formyl-5,6,7,8-tetrahydropyrimidino[1,2-alpha]purin-10(3H)-one; and the 1,N(2)-bicyclic adduct, 3-[2'-deoxy-3',5'-O-bis(tert-butyldimethylsilyl)-beta-D-erythropentafuranosyl]-3,5,6,7-tetrahydro-6-hydroxy-7-(ethane-2"-al)-9H-imidazo[1,2-alpha]purine-9-one. The one-substituted and 1,N(2)-cyclic reaction products were unstable and rearranged over time to yield the 1,N(2)-bicyclic 2'-deoxyguanosine adducts. The desired reaction product was obtained as a mixture of four diastereomers by removing the tert-butyldimethylsilyl groups with hydrogen fluoride. This synthetic approach to the cis-2-butene-1,4-dial-derived dGuo adducts confirms our previous structural characterization of the in vitro cis-2-butene-1,4-dial-dGuo reaction product. These studies demonstrate that the observed 1,N(2) bicyclic structure is the thermodynamically stable isomer, supporting our previous observations that this adduct is the major product formed in vitro. Finally, these studies provide the necessary groundwork for the preparation of oligonucleotides with site specifically incorporated cis-2-butene-1,4-dial-derived adducts.     

Development of an affinity ligand for purification of alpha 2-adrenoceptors from human platelet membranes

Human platelets contain alpha 2-adrenoceptors which are negatively coupled to the enzyme adenylate cyclase. In order to better understand the interaction of this subtype of alpha receptor with this key enzyme, we have initiated a program to isolate and characterize the alpha 2-adrenoceptor. This report describes the synthesis and biological characterization of a series of molecules that were prepared as affinity ligands for this purpose. The best of these is 9-(allyloxy)-6-chloro-3-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine (SK&F 101253). This compound is an alpha 2-adrenoceptor antagonist, which was obtained by synthetic modification of 6-chloro-3-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine (SK&F 86466), a novel antagonist with high affinity for the alpha 2-receptor.     

Syntheses and properties of 1-methyl-3-phenylaminobenzimidazolium salts, models of DNA adducts of N7-arylaminodeoxyguanosinium salt

When arylaminating carcinogens are administered to cells, they mainly generate the C8-arylamino-2'-deoxyguanosine adduct in DNA. A mechanism for this was proposed in which N7-arylaminated 2'-deoxyguanosine acts as an intermediate; however, it remained unclear whether this is actually the case. To elucidate the mechanisms involved in the generation of this adduct, a series of 5-substituted 1-methylbenzimidazole derivatives were used as models of the imidazole moiety of 2'-deoxyguanosine. Syntheses of a series of 5-substituted (CH(3), H, F, CF(3), or NO(2)) 1-methyl-3-phenylaminobenzimidazolium salts (7) and their related compounds were carried out, and the chemical characteristics of these products were examined. Heating compound 7 at 80 degrees C for 48 h in H(2)O/MeOH provided 5-substituted 1-methyl-2-oxo-2, 3-dihydrobenzimidazoles but only when this compound contained a CF(3) or NO(2) substituent. Compound 7 decomposed in alkaline media, and its rate of decomposition increased when this compound had a stronger electron-withdrawing substituent. The product obtained under these conditions was 4-substituted N(1)-methyl-2-phenylazoaniline. On the other hand, when 1-methyl-3-(4-nitrophenylamino)benzimidazolium salt was treated under the same conditions as described above, it generated a demethylated product, 1-(4-nitrophenylamino)benzimidazole, when heated in H(2)O/MeOH and N(1)-formyl-N(1)-methyl-2-phenylazoaniline when treated in alkaline media. When the chemical characteristics of 3-phenylamino and 3-amino groups were compared using 3-substituted 1-methyl-5-(trifluoromethyl)benzimidazoles, the 3-phenylamino derivative was found to be more reactive.     

Enzymes in addition to CYP3A4 and 3A5 mediate N-demethylation of dextromethorphan in human liver microsomes

Both indinavir and troleandomycin (CYP3A inhibitors) are incapable of completely inhibiting dextromethorphan metabolism to 3-methoxymorphinan in human liver microsomes. It is hypothesized that CYPs in addition to CYP3A4 and 3A5 contribute to this biotransformation. The effect of CYP-selective inhibitors on the residual 3-methoxymorphinan activity in human liver microsomes (i.e. in the presence of 30 microM indinavir, a selective CYP3A4 and 3A5 inhibitor) was measured to identify these enzymes. At this concentration, indinavir completely inhibited the formation of 3-methoxymorphinan by rCYP3A4 and rCYP3A5. In addition, the formation kinetics of 3-methoxymorphinan in rCYPs was measured. Only CYP2B6, 2C8 and 2C18 were considered likely candidates as contributors to residual 3-methoxymorphinan activity. The residual 3-methoxymorphinan activity was highly correlated with CYP2B6 activity as measured by CYP2B6 antibody (r(2)=0.90, p<0.001) and by orphenadrine (r(2)=0.97, p<0.001), but was not correlated (r(2)=0.12, p>0.05) with CYP2C8 activity. Collectively, these findings suggest that CYP2B6 is a major contributor towards residual 3-methoxymorphinan activity, while CYP2C8 and 2C18 are either minor contributors or do not contribute to this metabolic process.     

Characterization of the adducts formed in the reactions of glycidamide with thymidine and cytidine

Glycidamide (GA) is a mutagenic epoxide metabolite of acrylamide (AM), a high production chemical with many industrial uses. Moreover, recent findings have shown that AM is formed in starchy foods cooked at high temperatures. This has refocused the attention on this chemical and its metabolite and on their possible mutagenicity and carcinogenicity. In this study, we have reacted GA with cytidine and thymidine in aqueous-buffered solutions. The adducts from the nucleosides have been isolated by reversed phase HPLC and characterized by their UV absorbance and 1H and 13C NMR spectroscopic and mass spectrometric features. The reaction with thymidine yielded one adduct, N3-(2-carbamoyl-2-hydroxyethyl)thymidine (N3-GA-dThd), while the reaction with cytidine yielded three adducts. Two adducts were identified as a diastereomeric pair of N3-(2-carboxy-2-hydroxyethyl)cytidine (N3-GA-Cyd-1 and N3-GA-Cyd-2). The third adduct from the cytidine reaction was identified as N3-(2-carboxy-2-hydroxyethyl)uridine (N3-GA-Urd).     

The role of oxidative stress on the effect of 1,4,7,10,13,16-hexathiacyclooctadecane on copper and zinc toxicity in HepG2 cells

Experiments have shown that 1,4,7,10,13,16-hexathiacyclooctadecane (L3) increased the Cu2+ toxicity on HepG2 cells, whereas the combination Zn(2+)/L3 was less toxic relative to the metal control. In all cases, glutathione (GSH) levels were decreased and vitamins C and E supplementation partially counteracted the increased toxicity in the Cu(2+)/L3-treated cells. The previously observed effects of this hexathiamacrocyclic ligand (L3) on the Cu2+ and Zn2+ toxicity were further investigated by first depleting the intracellular GSH levels by means of L-buthionine S,R-sulphoximine. Combined treatment with Cu(2+)/L3 resulted in complete cell death, whereas for Zn(2+)/L3 no severe effects were observed. Direct measurement of reactive oxygen species (ROS) revealed that Cu2+ induced a high degree of oxidative stress on the cells. This was not the case for Zn2+. The results proved a previously proposed mechanism in which GSH is used to conjugate the metal-ligand complex, but as a result of this, GSH is no longer available for inactivation of ROS. Also, both the intracellular copper and zinc content were determined for each experiment by means of inductively coupled plasma-atomic emission spectroscopy. According to these data, zinc is depleted in Cu(2+)/L3-treated cells, which could have consequences on superoxide dismutase and as a result of this on the amount of oxidative stress.     

Ca2+ permeability of the (alpha4)3(beta2)2 stoichiometry greatly exceeds that of (alpha4)2(beta2)3 human acetylcholine receptors

Human alpha4beta2 nicotinic acetylcholine receptors (AChRs) expressed in Xenopus laevis oocytes or transfected cell lines are present as a mixture of two stoichiometries, (alpha4)2(beta2)3 and (alpha4)3(beta2)2, which differ depending on whether a beta2 or alpha4 subunit occupies the accessory subunit position corresponding to beta1 subunits of muscle AChRs. Pure populations of each stoichiometry can be expressed in oocytes by combining a linked pair of alpha4 and beta2 with free beta2 to produce the (alpha4)2(beta2)3 stoichiometry or with free alpha4 to produce the (alpha4)3(beta2)2 stoichiometry. We show that the (alpha4)3(beta2)2 stoichiometry and the (alpha4)2(beta2)2beta3 and (alpha4)2(beta2)2alpha5 subtypes in which beta3 or alpha5occupy the accessory positions have much higher permeability to Ca2+ than does (alpha4)2(beta2)3 and suggest that this could be physiologically significant in triggering signaling cascades if this stoichiometry or these subtypes were found in vivo. We show that Ca2+ permeability is determined by charged amino acids at the extracellular end of the M2 transmembrane domain, which could form a ring of amino acids at the outer end of the cation channel. Alpha4, alpha5, and beta3 subunits all have a homologous glutamate in M2 that contributes to high Ca2+ permeability, whereas beta2 has a lysine at this position. Subunit combinations or single amino acids changes at this ring that have all negative charges or a mixture of positive and negative charged amino acids are permeable to Ca2+. All positive charges in the ring prevent Ca2+ permeability. Increasing the proportion of negative charges is associated with increasing permeability to Ca2+.     

Characterization of 3-epi-1alpha,25-dihydroxyvitamin D3 involved in 1alpha,25-dihydroxyvitamin D3 metabolic pathway in cultured cell lines

Using six different cultured cell models representing osteoblast, intestine, kidney and keratinocyte, we have demonstrated that 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) is metabolized into 3-epi-1alpha,25(OH)2D3 in vitamin D-target cells. Although differences existed in the amount of 3-epi-1alpha,25(OH)2D3 formed with different cell types, it was apparent that 1alpha,25(OH)2D3 was subjected to metabolism both through the C24-oxidation and 3-epimerization pathways. Time course and dose response studies showed that the production of 3-epi-1alpha,25(OH)2D3 was enzymatic. It is interesting to note that this epimerization proceeded from 3beta towards 3alpha unidirectionally, and this conversion was not inhibited by ketoconazole. These data suggest that cytochrome P450 related enzymes including the 24-hydroxylase would not affect this reaction. The biological activity of 3-epi-1alpha,25(OH)2D3 was found to be lower than the native 1alpha,25(OH)2D3 in suppressing of proliferation of HL-60 cells, while the affinity of 3-epi-1alpha,25(OH)2D3 for vitamin D-binding protein was 2.5-fold higher than that of 1alpha,25(OH)2D3. The results indicate that 3-epimerization may change the pharmacokinetics and catabolism of 1alpha,25(OH)2D3 in vitamin D-target cells.     

Regulation of bladder muscarinic receptor subtypes by experimental pathologies

1 The M3 muscarinic receptor subtype is widely accepted as the receptor on smooth muscle cells that mediates cholinergic contraction of the normal urinary bladder and other smooth muscle tissues, however, we have found that the M2 receptor participates in contraction under certain abnormal conditions. The aim of this study was to determine the effects of various experimental pathologies on the muscarinic receptor subtype mediating urinary bladder contraction. 2 Experimental pathologies resulting in bladder hypertrophy (denervation and outlet obstruction) result in an up-regulation of bladder M2 receptors and a change in the receptor subtype mediating contraction from M3 towards M2. Preventing the denervation-induced bladder hypertrophy by urinary diversion prevents this shift in contractile phenotype indicating that hypertrophy is responsible as opposed to denervation per se. 3 The hypertrophy-induced increase in M2 receptor density and contractile response is accompanied by an increase in the tissue concentrations of mRNA coding for the M2 receptor subtype, however, M3 receptor protein density does not correlate with changes in M3 receptor tissue mRNA concentrations across different experimental pathologies. 4 This shift in contractile phenotype from M3 towards M2 subtype is also observed in aged male Sprague-Dawley rats but not females or either sex of the Fisher344 strain of rats. 5 Four repeated, sequential agonist concentration response curves also cause this shift in contractile phenotype in normal rat bladder strips in vitro, as evidenced by a decrease in the affinity of the M3 selective antagonist p-fluoro-hexahydro-sila-diphenidol (p-F-HHSiD). 6 A similar decrease in the contractile affinity of M3 selective antagonists (darifenacin and p-F-HHSiD) is also observed in bladder specimens from patients with neurogenic bladder as well as certain organ transplant donors. 7 It is concluded that although the M3 receptor subtype predominantly mediates contraction under normal circumstances, the M2 receptor subtype can take over a contractile role when the M3 subtype becomes inactivated by, for example, repeated agonist exposures or bladder hypertrophy. This finding has substantial implications for the clinical treatment of abnormal bladder contractions.     

盐酸头孢唑兰合成路线图解

本文综述了盐酸头孢唑兰的合成路线,主要包括以7β-氨基-3-（3-氧代丁酰氧甲基）-2-头孢烯-2-羧酸（7-AACA）、7β-（5-氨基-5-羧基戊酰胺基）3-羟甲基-2头孢烯-2-羧酸（DCPC）或7B-氨基-3-乙酰氧甲基-2-头孢烯一2-羧酸（7-ACA）为起始原料的多条合成路线。因原料7-AACA和DCPC在国内不易获得,故以7-ACA为起始原料合成盐酸头孢唑兰为宜。