3-氨基-2-羟基-4-苯基丁酸合成路线图解

3-氨基 - 2 -羟基 - 4-苯基丁酸 ( 3- amino- 2 - hydrox-y- 4- phenylbutyric acid,AHPA,1 )是一种重要的非天然氨基酸 ,具有多种潜在的生物活性 ,亦是合成免疫增强剂 bestatin[1]和强效抗 HIV蛋白酶活性化合物 kynostatins[2 ] (如 KNI- 2 72、KNI- 2 2 7、KNI- 5 77等 )以及某些肾素抑制剂 [3 ]的关键中间体。本文对其合成工艺路线作出简要评述 ,现归纳如下。1　苯丙氨酸法A[4] :苯丙氨酸 ( 2 )与苄氧羰酰氯 ( Z- Cl)反应生成 3,再与 3,5 -二甲基吡唑 ( DMP)缩合得 4,经Li Al H4还原生成醛 5 ,与 Na HSO3 和 KCN生成氰醇 6,…     

药物中间体2-(2’-羟基-4’-氨基苯基)苯并噻唑的合成工艺改进

目的改进2-(2’-羟基-4’-氨基苯基)苯并噻唑的合成工艺。方法以邻氨基苯硫酚与对氨基水杨酸为原料,对该反应的合成方法进行改进。结果将反应收率由50%提高至81.7%,反应温度由150℃降至50℃,反应时间由3 h缩短至45 min。结论改进工艺既降低了成本,又增加了反应的环境友好性。     

1-乙酰基-4-(4-羟基苯基)哌嗪的合成

目的对抗真菌药酮康唑的重要中间体1-乙酰基-4-(4-羟基苯基)哌嗪的合成工艺进行研究。方法以六水合哌嗪和对氯硝基苯为原料合成目标化合物,并对工艺进行探索。结果得到目标化合物,总产率优于现行路线。结论该路线有希望用于工业化生产。     

1-乙酰-4-(4-羟基苯基)哌嗪合成的改进

二乙醇胺经溴化、环合一锅合成 N-(4-甲氧苯基)哌嗪氢溴酸盐(3),解决了劳动保护问题。酰化收率经改进从26%提高至70%以上,总收率26.4%,适合工业生产。     

(S-2-乙氧基-3-(4-羟基苯基)丙酸乙酯的合成

L-酪氨酸经O-苄基化和重氮化反应制得（S）-2-羟基-3-（4-苄氧苯基）丙酸，再进行O-乙基化及乙酯化得到（S）-2-乙氧基-3-（4-苄氧苯基）丙酸乙酯，续经催化氢化脱苄基得到手性中间体（S）-2-乙氧基-3-（4-羟基苯基）丙酸乙酯，总收率19％，ee值98．5％。     

2-(3-氰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯的合成

目的优化非布司他关键中间体2-(3-氰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(4)的合成方法。方法采用"一勺烩"方法,以4-羟基苯甲腈为起始原料,首先与硫氢化钠和无水氯化镁在N,N-二甲基甲酰胺中反应,所得中间体不经分离,直接加入2-氯乙酰乙酸乙酯进行环合反应,得到2-(4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(2);然后通过六亚甲基四胺/三氟乙酸进行Duff反应,得到2-(3-甲酰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯(3);再经盐酸羟胺/甲酸/甲酸钠体系脱水得到目标化合物。结果经四步反应合成非布司他关键中间体4,总收率为22.6%,其结构经核磁共振氢谱、质谱确证。结论改进后的工艺终产品无需柱色谱纯化,适合工业化生产。     

4-氯-2-羟基苯乙酮的合成

以3-氨基苯酚为原料,经酰化、甲基化反应和Fries重排反应制得N-(4-乙酰基-3-羟基苯基)乙酰胺,再经去乙酰化、重氮化和Sandmeyer反应得到4-氯-2-羟基苯乙酮,总收率约44%.     

(E)-3-(4-羟基-2-甲氧基苯基)丙烯酸甲酯的合成

4-羟基-2-甲氧基苯甲醛和丙二酸在吡啶和苯胺催化下,经Knoevenagel缩合反应制得(E)-3-(4-羟基-2-甲氧基苯基)丙烯酸,再在1-(3-二甲胺基丙基)-3-乙基碳二亚胺盐酸盐和4-二甲胺基吡啶作用下与甲醇成酯制得(E)-3-(4-羟基-2-甲氧基苯基)丙烯酸甲酯,总收率为58.5％.     

化合物3,4,5-三羟基-N-[2-(4-羟基苯基)乙基]苯甲酰胺的抗氧化活性

目的对化合物3,4,5-三羟基-N-[2-(4-羟基苯基)乙基]苯甲酰胺(3,4,5-trihydroxy-N-[2-(4-hydroxyphenyl)ethyl]-benzamide,THHEB)的抗氧化活性进行研究。方法通过测定对有机自由基1,1-二苯基苦基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)的清除能力、6-羟基-2,5,7,8-四甲基苯并二氢吡喃-2-羧酸(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid,Trolox)当量抗氧化能力(trolox-equivalent antioxidant capacity assay,TEAC),测定超氧自由基的清除活性实验、脂质过氧化法以及羟基自由基诱导DNA损伤的方法评价THHEB的抗氧化活性。结果5种方法检测结果均显示,THHEB具有很强的清除自由基的活性。其中,THHEB对稳定自由基DPPH和超氧自由基的清除能力超过抗坏血酸的相应活性,其IC50值分别为22.8、2.5μmol.L-1。用TEAC方法测定THHEB总的抗氧化能力大约为0.6,也比L-抗坏血酸相应值高。脂质过氧化法测定的THHEB活性要弱于著名的抗氧化化合物2,6-二叔基对甲苯酚(butylated hydroxytoluene,BHT)。此外,非常小浓度比如4μmo.lL-1的THHEB对羟基自由基导致的pBR322 DNA链断裂具有显著的保护作用。结论THHEB具有很强的清除自由基的活性。     

HPLC法测定脑心舒口服液中10-羟基-2-癸烯酸的含量

目的:建立脑心舒口服液中10-羟基-2-癸烯酸的含量测定方法.方法:高效液相色谱法,迪马C18(150mm×4.6mm),乙腈:0.1%磷酸溶液(22:78)为流动相;检测波长为207nm.结果:10-羟基-2-癸烯酸的峰面积和浓度呈良好的线性关系,线性范围为2.525μg/ml～50.5μg/ml,回归方程:A=457.07C-92814.r=0.9996.平均回收率为X=99.01%,RSD=0.33%.结论:本方法专属性强、操作简便.结果准确可靠.     

Uptake of 4-chloro-2-methylphenoxyacetic acid (MCPA) from the apical membrane of Caco-2 cells by the monocarboxylic acid transporter

The cellular uptake mechanism of 4-chloro-2-methylphenoxyacetic acid (MCPA), a phenoxyacetic acid derivative, was investigated using Caco-2 epithelial cells. The cells were incubated with 50 microM MCPA at pH 6.0 and 37 degrees C, and the uptake of MCPA from the apical membranes was measured. The uptake of MCPA was significantly decreased by incubation at low temperature (4 degrees C) and markedly increased by lowering the extracellular pH. Pretreatment with a protonophore, carbonylcyanide-p-(trifluoromethoxy)phenylhydrazone (25 microM), or metabolic inhibitors, 2,4-dinitrophenol (1 mM) and sodium azide (10 mM), significantly decreased the uptake of MCPA by 53%, 45% and 48%, respectively. Coincubation of MCPA with 10 mM l-lactic acid or alpha-cyano-4-hydroxycinnamate, which is a substrate or an inhibitor of the monocarboxylic acid transporters (MCTs), significantly decreased the uptake of MCPA by 31% and 20%, respectively, and coincubation with benzoic acid profoundly decreased the uptake by 68%. In contrast, coincubation with succinic acid (a dicarboxylic acid) did not affect the uptake. Kinetic analysis of initial MCPA uptake suggested that MCPA is taken up via a carrier-mediated process [Km=1.37+/-0.15 mM, Vmax=115+/-6 nmol (mg protein)(-1) (3 min)(-1)]. Lineweaver-Burk plots show that benzoic acid competitively inhibits the uptake of MCPA with a Ki value of 4.68 +/-1.76 mM. A trans-stimulation effect on MCPA uptake was found in cells preloaded with benzoic acid. These results suggest that the uptake of MCPA from the apical membrane of Caco-2 cells is mainly mediated by common MCTs along with benzoic acid but also in part by l-lactic acid.     

4-氨基-5-氯-2-乙氧基苯甲酸的合成

目的合成4-氨基-5-氯-2-乙氧基苯甲酸。方法以对氨基水杨酸钠为原料,经酸化、甲酯化、乙酰化、乙基化、氯代、水解等六步反应得到枸橼酸莫沙必利的主要中间体4-氨基-5-氯-2-乙基苯甲酸。结果与结论本合成工艺提高了收率,降低了成本,更适合工业化生产,本工艺总收率为62.4%。     

HPLC法同时测定尿多酸肽注射液中4-羟基苯乙酸及5-羟基吲哚乙酸的含量

目的　以HPLC法同时测定尿多酸肽注射液中4 - 羟基苯乙酸及5 - 羟基吲哚乙酸的含量。方法　采用MightysilRP C1 8(2 5 0mm×4 . 6mm ,5 μm)色谱柱,以1 %的甲酸溶液为流动相A ,乙腈为流动相B ,梯度洗脱,柱温30℃,流量1ml·min-1 ,检测波长2 82nm。结果　4 羟基苯乙酸在1 .0～1 4 0 . 0 μg·ml-1 范围内,色谱峰面积与对照品浓度呈现良好的线性关系,r=1 . 0 0 0 ;平均回收率为1 0 0 . 7%(RSD为0 . 6 %,n =9)。5 羟基吲哚乙酸在0 .1～2 0 . 0 μg·ml-1 范围内,色谱峰面积与对照品浓度呈现良好的线性关系,r=1 . 0 0 0 ;平均回收率为99 .7%(RSD为0 .6 %,n =9)。结论　该方法灵敏度高,准确,选择性、重复性好。     

HPLC法同时测定尿多酸肽注射液中4-羟基苯乙酸及5-羟基吲哚乙酸的含量

目的 以HPLC法同时测定尿多酸肽注射液中4-羟基苯乙酸及5-羟基吲哚乙酸的含量。方法 采用Mightysil RP-C₁₈(250mm×4.6mm,5μm)色谱柱,以1%的甲酸溶液为流动相A,乙腈为流动相B,梯度洗脱,柱温30℃,流量1ml·min^-1,检测波长282nm。结果 4-羟基苯乙酸在1.0～140.0μg·ml^-1范围内,色谱峰面积与对照品浓度呈现良好的线性关系,r=1.000;平均回收率为100.7%(RSD为0.6%,n=9)。5-羟基吲哚乙酸在0.1～20.0μg·ml^-1范围内,色谱峰面积与对照品浓度呈现良好的线性关系,r=1.000;平均回收率为99.7%(RSD为0.6%,n=9)。结论 该方法灵敏度高,准确,选择性、重复性好。     

Synthesis of L-2-amino-4-hexynoic acid and derivatives

A synthesis is described of optically pure L-2-amino-4-hexynoic acid and its derivatives, which can serve as potentially useful precursors for the preparation of highly tritium labeled norleucine-containing peptides, as well as other side-chain modified peptides. Catalytic tritiation of one derivative of this acetylenic amino acid afforded the (³H)-L-norleucine derivative with a specific activity of 115 ± 5 Ci/mmol.     

An innovative approach to the analysis of 3-[4-(2-methylpropyl)phenyl]propanoic acid as an impurity of ibuprofen on a carbon-coated zirconia stationary phase

3-[4-(2-Methylpropyl)phenyl]propanoic acid has been introduced as impurity F to the European Pharmacopoeia in its Supplement 4.2. In contrast to other impurities, which are evaluated by HPLC, the content of impurity F is determined by gas chromatography after previous derivatization. Thus a novel reversed-phase HPLC method was developed to simplify the evaluation of pharmacopoeial impurity F of ibuprofen. Favourable properties of zirconia stationary phases were employed for this purpose. The HPLC separation was achieved on a Zr-CARB column (150 mm × 4.6 mm i.d., 5 μm) using the mobile phase acetonitrile–phosphate buffer (pH 3.5, 25 mM) (38:62, v/v), temperature 80 °C and the flow rate 1.2 ml min⁻¹. The fluorescence detection was employed to enhance the sensitivity of the method. Optimal detection parameters were chosen on the basis of fluorescence spectra of the analytes. The excitation and emission wavelengths were 220 nm and 285 nm, respectively. The analysis was completed within 25 min. The subsequent validation of the method confirmed the applicability of method for the analytical assay of impurity F.     

Binding of a metabolite of triflusal (2-hydroxy-4-trifluoromethylbenzoic acid) to serum proteins in rat and man

Summary 2-hydroxy-4-trifluoromethylbenzoic acid (HTB) is the main active metabolite of the platelet anti-aggregant drug triflusal. Its binding to plasma proteins of rats and healthy volunteers in vitro and in vivo has been studied.Rats were given a single oral dose of 50 mg·kg^–1 triflusal and the healthy volunteers received 300 mg as a single oral dose or a multiple dose regimen of 600 mg every 24 h and 300 mg every 8 h, both for 13 days. Protein-free HTB was obtained by ultrafiltration. Unbound and total HTB concentrations were determined by HPLC.HTB was primarily bound to albumin in plasma. The Scatchard plots suggested two types of binding sites for HTB on the albumin molecule. In rats, the binding constants (K=intrinsic affinity constant, n=number of binding sites) were K₁=1.4×10⁵ l·mol^–1, n₁=1.23, and K₂=4.1×10³ l·mol^–1 and n₂=3.77. The mean plasma concentration in rats after oral administration was 185 (37) g·ml^–1 (protein-free HTB: 2.44 (0.77)%). The binding constants in human plasma were K₁=4.7×10⁵ l·mol^–1, n₁=1.93, K₂=4.3 l·mol^–1 and n₂=4.28.The plasma HTB concentration in man (n=8) was 35 g·ml^–1 (C_max) after a single oral dose of triflusal 300 mg, 172.96 g·ml^–1 (C_max·ss) during the multiple dosage regimen of 300 mg every 8 h, and 131 g·ml^–1 (C_max·ss) during the multiple oral dose regimen of 600 mg every 24 h. Unbound HTB ranged from 0.27 to 0.43%, depending on dose. HTB had high affinity for plasma albumin, which was not saturable after therapeutic doses. It showed linear elimination.     

Effect of 2-Hydroxy-4-methoxy Benzoic Acid Isolated from Hemidesmus indicus on Erythrocyte Membrane Bound Enzymes and Antioxidant Status in Streptozotocin-induced Diabetic Rats

In the present study, the effect of 2-hydroxy-4-methoxy benzoic acid isolated from roots of Hemisdesmus indicus on the erythrocyte membrane bound enzymes and antioxidant status in streptozotocin-induced diabetic rats was investigated. The streptozotocin-induced diabetic rats were treated with 2-hydroxy-4-methoxy benzoic acid (500 μg/kg/day) for 7 weeks by oral intubation and compared with glibenclamide, a standard hypoglycemic agent (100 mg/kg). The erythrocyte membrane was isolated and the activity of Na⁺/K⁺-dependent ATPases, Ca²⁺-ATPases, Mg²⁺-ATPases were determined. Superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, vitamins C, vitamin E, plasma reduced glutathione and erythrocyte glutathione, reduced glutathione content in the tissues was also assayed. Administration of 2-hydroxy-4-methoxy benzoic acid to diabetic rats significantly (F>0.05 and P<0.001) elevated the activity of total ATPases, Na⁺/k⁺ ATPase, Mg²⁺ ATPase and Ca²⁺ ATPase to near normal level. The activities of catalase, superoxide dismutase and glutathione peroxidase and glutathione-S-transferase in erythrocytes were decreased significantly (F>0.05; P<0.001) in diabetic rats. Diabetic rats treated with 2-hydroxy-4-methoxy benzoic acid showed a significant (F>0.05; <0.001) increase in the enzymic antioxidants in erythrocytes. The elevated levels of vitamin E and low level of vitamin C and glutathione level in plasma and erythrocytes were observed in diabetic rats when compared to control rats and were restored significantly (F>0.05; P<0.001) after the administration of 2-hydroxy-4-methoxy benzoic acid. This study concludes administration of 2-hydroxy-4-methoxy benzoic acid supports the restoration of antioxidant defence, reduces the free radial production, lipid peroxidation and the glycosylation of haemoglobin in diabetic rats.     

RP-HPLC法测定余甘子中诃黎勒酸、没食子酸、粘酸-2-O-没食子酸酯的含量

目的:建立RP-HPLC法同时测定余甘子(Phyllanthus emblica L.干燥成熟果实)中诃黎勒酸、没食子酸、粘酸-2-O-没食子酸酯含量。方法:采用Diamonsil C18柱(250 mm×4.6 mm,5μm),以甲醇-0.2%醋酸水溶液(19:81,v/v)为流动相;检测波长为275 nm;流速为1 mL.min-1;柱温为30℃。结果:诃黎勒酸、没食子酸、粘酸-2-O-没食子酸酯线性范围分别为0.235～1.176μg、0.185～0.924μg、0.418～2.09μg;平均回收率(n=6)分别为101.5%,99.20%,101.5%。结论:建立的方法简便,重现性好,可用于余甘子中诃黎勒酸、没食子酸、粘酸-2-O-没食子酸酯的含量测定。