Synthesis and Characterization of Metabolites and Potential Impurities of the Antiulcerative Drug Tenatoprazole

Tenatoprazole (Ulsacare^®) is a recently developed antiulcerative drug used for the treatment of both erosive and nonerosive gastroesophageal reflux disease. During the bulk synthesis of tenatoprazole, we have observed four impurities (tenatoprazole N‐oxide, tenatoprazole sulfone N‐oxide, N‐methyl tenatoprazole, and desmethoxy tenatoprazole) and two metabolites (tenatoprazole sulfide and tenatoprazole sulfone). The present work describes the synthesis and characterization of these impurities.     

Synthesis and Characterization of Metabolites and Potential Impurities of Balsalazide Disodium,an Anti-Inflammatory Drug

Balsalazide disodium (Colazide®) is an oral prodrug of mesalamine (5-aminosalicylic acid) and possesses anti-inflammatory properties. During the process development for balsalazide disodium, we observed eight impurities, namely des-β-alanine balsalazide, balsalazide β-alanine, balsalazide 3-isomer, decarboxy balsalazide, bis-azo salicylic acid, biphenyl-azo salicylic acid, bis-azo diacid, and bis-azo triacid. The present work describes the synthesis and characterization of these impurities.     

Synthesis of Metabolites and Related Substances of Rabeprazole,an Anti-Ulcerative Drug

Rabeprazole sodium (Aciphex®) is a gastric proton pump inhibitor used for the prevention and treatment of gastric acid–related diseases. During the synthesis of bulk drug of rabeprazole sodium, we have observed metabolites rabeprazole sulfide and rabeprazole sulfone and related substances rabeprazole-N-oxide, rabeprazole sulfone-N-oxide, N-aralkyl rabeprazole, chloro rabeprazole, and methoxy rabeprazole as impurities in the drug substance. The present work describes the synthesis and characterization of these compounds.     

Synthesis and Characterization of Potential Impurities of the Antimigraine Drug,Rizatriptan Benzoate

Rizatriptan benzoate is a recently developed antimigraine drug used for the treatment of migraines and severe headaches. In the synthesis of rizatriptan benzoate in bulk,various impurities are formed. The present work details the development of a simple and novel process for the preparation of hydrazone impurity (6), rizatriptan N‐oxide (7), rizatriptan dimer (9), desmethyl rizatriptan (13), 5‐(1H‐1,2,4‐triazol‐1‐yl‐methyl)‐1H‐indole‐3‐ethanamine hydrochloride (14), N‐methyl rizatriptan oxalate (15), and impurities.     

Synthesis and Spectral Characterization of Related Substances of Lacidipine,an Antihypertensive Drug

Five related substances (impurities) were detected in lacidipine bulk drug substance by a simple high-performance liquid chromatographic method (HPLC) and were identified by liquid chromatography–mass spectrometry (LC-MS). These related substances were independently synthesized, characterized, and co-injected with the sample containing impurities.     

Synthesis and Spectral Characterization of Related Substances of Vardenafil,an Erectile Dysfunction Drug

Abstract

Vardenafil hydrochloride trihydrate (Levitra) is used to treat erectile dysfunction (ED) and is an inhibitor of phosphodiesterase type 5 (PDE-5) enzyme. It maintains higher levels of cyclic guanosine monophosphate (cGMP), relaxes smooth muscles, promotes penile blood flow, and enhances erectile function. During the bulk drug synthesis of vardenafil hydrochloride trihydrate, six related substances (impurities), vardenafil dimer, vardenafil N-oxide, vardenafil glycene, vardenafil oxopiperazine, vardenafil oxoacetic acid, and phenyl vardenafil were identified, and these are reported herein for the first time. The present work describes the synthesis and characterization of these impurities.     

Synthesis of Potential Impurities of Bicalutamide

Bicalutamide is an oral nonsteroidal, anti-androgen drug used for prostate cancer. It binds to the androgen receptor. During the bulk synthesis of bicalutamide, various impurities are formed. The present work details the development of simple processes for the preparation of impurities of bicalutamide, viz bical-sulfoxides (6), bical-deshydroxy (10), bical-desfluoro (10a), bical-2-fluoro (10b), and bical-3-fluoro (10c).     

Physicochemical Investigation of Engineered Nanosuspensions Containing Model Drug,Lansoprazole

Lansoprazole is a proton-pump inhibitor used in treatment of gastric ulcers, gastroesophageal reflux disease (GERD), and Zollinger–Ellison syndrome. The objective of the study was physicochemical investigation and comparative characterization of nanosuspensions of lansoprazole by complexing with β-cyclodextrin and β-cyclodextrin-based nanosponges to enhance its solubility and stability. Inclusion complexes of lansoprazole with β-cyclodextrin and nanosponges were prepared by physical method and polymer condensation method, respectively. Particle size, zeta potential, encapsulation efficiency, in vitro release, FTIR, and Differential Scanning Calorimeter (DSC) studies were used as characterization parameters. The average particle size of lansoprazole nanoparticles was found to be in the range of 178.7 ± 6.39 nm to 204.9 ± 2.91 nm. The high zeta potential values were attained to ensure a high-energy barrier and favor a good stability of nanosuspensions. In vitro release study showed the controlled release of lansoprazole, which was more satisfactory than individual drug. FTIR spectroscopy showed that there was interaction of cyclodextrin and its nanosponges with drug. DSC study revealed that drug was involved in complexion with cyclodextrin and nanosponges. Solubility and stability of lansoprazole were remarkably improved by inclusion complexation. Based on these findings, it can be concluded that engineered nanosuspension of lansoprazole is a promising carrier for nanoparticulate drug delivery in gastric ulcer.     

兰索拉唑的合成工艺改进

以甲醇钠为缩合剂,2-氯甲基-3-甲基-4-(2,2,2-三氟乙氧基)吡啶盐酸盐与2-巯基苯并咪唑缩合,高收率(97%)地获得硫醚化合物(3);以过氧化氢-钼酸铵体系催化氧化3制得兰索拉唑,收率达81%。其结构经1H NMR和MS确证。     

新型双核锌席夫碱配合物的合成及其结构表征

新型双核锌席夫碱配合物的合成及其结构表征;席夫碱; 双核锌配合物; 合成; 谱学表征; 构象分析     

可能用于光动力诊疗的2-硝基咪唑卟啉衍生物的合成及表征

从吡咯和对羟基苯甲醛等起始原料出发,设计合成了4种具有潜在肿瘤乏氧检测及光动力治疗作用的2-硝基咪唑修饰新型卟啉衍生物.目标化合物结构经紫外、红外、质谱和核磁确证.     

哌啶并噻吩并嘧啶酮衍生物的合成、表征及生物活性

应用中间体碳二亚胺分别与伯胺、仲胺及醇在醇钠催化条件下合成9个未见报道的新型哌啶并噻吩并嘧啶酮衍生物.产物的结构经元素分析、1H NMR、MS及单晶X衍射检测得以确认.探讨了所有化合物的杀菌活性,结果表明部分化合物表现出较好的抑菌活性,其中化合物7b对黄瓜灰霉、水稻纹枯、小麦赤霉的抑制率分别为76.19%,68.83%和56.52%.     

取代苯甲醛双缩二氨基硫脲的合成与表征

合成了9个新的取代苯甲醛双缩二氨基硫脲化合物,其结构均经^1H NMR,IR和元素分析表征。     

烯丙基砜的合成与表征

以三种烯丙醇为起始原料 ,经溴代生成烯丙基溴 ,然后与无水苯亚磺酸钠发生亲核取代反应生成烯丙基砜。烯丙基溴与烯丙基砜在相转移催化下的偶联反应也可合成新的烯丙基砜。作者用这两种方法合成了六种烯丙基砜。初步探讨了反应温度 ,催化剂等对反应的影响。产物结构经IR ,1 HNMR等波谱分析确证。     

乙基二苯甲酰甲烷的合成及表征

乙基二苯甲酰甲烷是一种光吸收性能良好的化合物。该法以苯甲酸乙酯和苯乙酮为起始原料,经克莱森缩合生成二苯甲酰甲烷,再与溴乙烷进行烷基化反应,最后生成乙基二苯甲酰甲烷,并对合成产物进行结构分析及紫外光吸收性能表征。     

对苯双酰腙类化合物的合成与表征

以对苯二甲酸为起始原料,设计合成了5个新型的对苯双酰腙类化合物,其结构经1H NMR,MS和元素分析表征。     

几种Cardo聚芳醚砜的合成与表征

酚酞型聚芳醚砜(PES-C)是综合性能优异的热塑性工程塑料,可通过溴化、磺化等改性.本文用一步法,K₂C0₃存在下以二甲基亚矾为介质,合成了不同取代烷基的聚合物.     

硅胶表面接枝手性树枝状大分子的合成与表征

以氨丙基硅胶为核,通过与丙烯酸甲酯和乙二胺进行多次重复的Michael加成反应以及酰胺化反应制得在硅胶表面接枝的树枝状大分子(G);G进一步通过L-苯丙氨酸(L-Phe)的手性修饰得到在硅胶表面接枝的手性树枝状大分子(G-L-Phe).G和G-L-Phe的结构经~(13)C NMR,IR及SEM表征.     

1，1-双二茂铁基烷的合成与表征

1;1-双二茂铁基烷的合成与表征;缩合;双二茂铁基烷;合成;表征     

双丙炔醇酯类化合物的合成与表征

合成了5个新的二丙炔醇酯类化合物[(CO2CH2C≡CH)2(1),CH2(CO2CH2C≡CH)2,(2),(CH2CO2CH2C≡CH2)(3),(CHCO2CH2C≡CH)2,(4),C6H4-1,4-(CO2CH2C≡CH)2,(5)]，并对其进行了C／H，IR和^1H NMR等表征。