Lansoprazole

1 SYNTHESIS OF (R)-2-[[[3-METHYL-4-(2,2,2-TRIFLUOROETHOXY)-2-PYRIDYLJMETHYL] SULFINYL] -1H-BENZIMIDAZOLE (R)-(+)-LANSOPRAZOLE  

A 25 mL round-bottomed flask equipped with a magnetic stirrer bar was charged with WO3 (0.012 g, 0.05 mmol), (DHQD)2-PYR (0.088 g, 0.1 mmol) and 2-[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridyl]methylthio]-17/-benzimi-dazole (0.353 g, 1 mmol) in tetrahydrofuran (2mL) and the mixture was cooled to 0°C. To this was added dropwise aq. 30 % H2O2 (0.17 mL, 1.5 mmol) and the reaction mixture was stirred at 0 °C for 50 h (monitored by TLC). 

After completion, the reaction mixture was filtered through a sintered funnel to recover the catalyst, the filtrate diluted with EtOAc (20 mL) and washed with water and brine. The organic layer was dried over anhydrous Na2S04 and concentrated under reduced pressure. 

The crude reaction mixture was purified by column chromatography by using petroleum ether EtOAc (6 4—5 5 ) as eluent to afford (R)-lansoprazole (0.312 g, 84 %) as well as (DHQD)2-PYR (0.084 g). Recovered catalyst and ligand were reused without any loss in activity and selectivity. 

KINETIC RESOLUTION OF RACEMIC SULEOXIDES (FIGURE 9.4) 9.3.2 SYNTHESIS OE (R)-(+)-PHENYL BENZYL SULFOXIDE 

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Pantoprazole and tenatoprazole bind only to both the cysteines in M5/M6, cysteine 813 and 822, and lansoprazole binds to cysteine 321 in M3/M4 and to cysteine 813 in M5/M6, and cysteine 892 in M7/M8. These data suggest that, of the 28 cysteines in the a-subunit, only the cysteines present in the M5/M6... 

The proton pump inhibitors are contraindicated in patients who have hypersensitivity to any of the drags. Omeprazole (Pregnancy Category C) and lansoprazole, rabeprazole, and pantoprazole (Pregnancy Category B) are contraindicated during pregnancy and lactation. The proton pump inhibitors are used cautiously in older adults and in patients with hepatic impairment. 

There is a decreased absorption of lansoprazole when it is administered with sucralfate Lansoprazole may decrease tiie effects of ketoconazole, iron salts, and digoxin. When lansoprazole is administered with theophylline, there is an... 

Lansoprazole—Take tiie drug before meals. Swallow tiie capsules whole Do not chew, open, or crush. If you have difficulty swallowing the capsule, open and sprinkle granules on tfell-O or applesauce You will need regular medical check-ups while taking this drug. 

C Hi4F,N30S 103577-40-S) see Lansoprazole methyl N-[[5-(trifluoromethyl)-6-methoxy-l-naphthyl]-carbonyl]-A -methyIglycinate (C 7H ftF,N04 84533-46-0) see Tolrestat... 

Omeprazole 20-40 mg enterally daily ° Esomeprazole 20-40 mg enterally daily or ql2h ° Lansoprazole 30 mg enterally or IV daily ° Pantoprazole 40 mg enterally or IV daily or 12h ° Rabeprazole 20 mg enterally daily... 

H2 receptor antagonists (Cimetidine, famotidine, nizatidine, ranitidine) Proton pump inhibitors Lansoprazole Omeprazole Pantoprazole Rabeprazole... 

PPIs (taken once daily) for 4-8 weeks - Esomeprazole 20 mg - Lansoprazole 1 5-30 mg - Omeprazole 20 mg - Pantoprazole 40 mg - Rabeprazole 20 mg therapy. 

Lansoprazole 30 mg patients with atypical symptoms, complicated... 

Comparable daily doses of PPIs are omeprazole 20 mg = esomeprazole 20 mg = lansoprazole 30 mg = rabeprazole 20 mg = pantoprazole 40 mg. The PPIs degrade in acidic environments and are therefore formulated in delayed-release capsules or tablets.16 Lansoprazole, esomeprazole, and omeprazole contain enteric-coated (pH-sensitive) granules in a capsule form. For patients unable to swallow the capsule or in pediatric patients, the contents of the capsule can be mixed in applesauce or placed in orange juice. If a patient has a nasogastric tube, the contents of an omeprazole capsule can be... 

Pantoprazole, lansoprazole, and esomeprazole are available in intravenous formulations, which offer an alternative route for patients unable to take oral medications. The intravenous product is not more effective than the oral forms and is significantly more expensive. 

While generally not of major concern, omeprazole may inhibit the metabolism of warfarin, diazepam, and phenytoin lansoprazole may decrease theophylline concentrations. Drug interactions with omeprazole are of particular concern in patients who are considered slow metabolizers, as are approximately 3% of the Caucasian population. Unfortunately, it is unclear which patients have the polymorphic gene variation that makes them slow metabolizers.17 The metabolism of esomeprazole may also be altered in patients with this polymorphic gene variation. Patients on potentially interacting drugs should be monitored for development of drug-related problems. 

Welage LS, Berardi RR. Evaluation of omeprazole, lansoprazole, pantoprazole, and rabeprazole in the treatment of acid-related disorders. J Am Pharm Assoc 2000 40 52-62. 

The histamine2-receptor antagonists or H2RAs (cimetidine, famotidine, nizatidine, and ranitidine) and proton pump inhibitors (omeprazole, esomeprazole, lansoprazole, pantopra-zole, and rabeprazole) reduce the amount of acid secreted into the stomach by gastric parietal cells. These agents are also helpful for nausea and vomiting related to gastric acid secretion. 

Esomeprazole (Nexium) Lansoprazole (Prevacid) Omeprazole (Prilosec) Panloprazole (Protonix) Rabeprazole (Aciphex)... 

Ogasrtro (Lansoprazole) Duodenal ulcer Gastro-oesophageal reflux Helicobacter infections 2.3 0.8 1994 - UK 1995 - US Once daily, except when used as part of combination therapy for H. pylori and for hypersectetory conditions. Twice-daily when dose >120 mg. 

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