Ramosetron

Molecular formula C17H17N3O Molecular weight 279.34 CAS Registry No 132036-88-5 Merck Index 13, 8195 

Sample preparation Shake 1 (animal) or 2 (human) mL plasma or 1 mL urine with 200 [xL 100 [xg/mL IS in water, 1 mL saturated sodium bicarbonate, and 5 mL ethyl acetate for 15 min, centrifuge at 1200 g for 10 min. Remove the organic layer and add it to 2.5 mL 400 mM HCl, shake for 15 min, centrifuge at 800 g for 5 min. Remove the aqueous layer, add 2 mL saturated sodium bicarbonate solution to the aqueous layer, stir, let stand at room temperature for 20 min, add 4.5 mL ethyl acetate, shake for 15 min, centrifuge at 800 g for 5 min. Evaporate the organic layer to dryness under reduced pressure, reconstitute the residue with 100 xL mobile phase, inject a 60 xL aliquot. 

Mobile phase MeCNilOOmM potassium dihydrogen phosphate 100 mM phosphoric acid 25 37.5 37.5 (plasma) or MeCN 100 mM potassium dihydrogen phosphate 100 mM phosphoric acid 33 33 33 containing 400 xM sodium dodecyl sulfate (urine) 

Internal standard GSA 110 (9-methyl-3-[(5-methylimidazole-4-yl)methyl]-2,3,4,9-tetrahydrothiop5rrano[2,3-b]mdole-4-one himarate) (14) 

Takeshige, T. Kobayashi, S.-i. Higuchi, S. A simple method for the determination of YM060 in plasma and urine by high performance hquid chromatography, Biomed.Chromatogr., 1994, 8, 103-104. 

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CN (R)-(l-methyl-l//-indol-3-yl)(4,5,6,7-tetrahydro-177-benzimidazol-5-yl)methanone monohydrochloride ramosetron... 

Yahagi, R., Machida, Y., and Onishi, H., Mucoadhesive suppositories of ramosetron hydrochloride utilizing Carbopol, Int. J. Pharm., 193 205-212 (2000). 

C9HRamosetron hydrochloride /V-methyl-l//-indolc-5-methanesull onamidc (C 0H 2N2O2S 103628-43-9) see Sumatriptan... 

Oral ramosetron 0.1 mg without water has been compared with oral granisetron 2 mg with water given 1 hour before infusion of chemotherapy in a multicenter, randomized, single-blind, crossover study in 73 patients with cancer... 

Although the incidence of adverse effects was similar in the two groups, significantly more patients who received granisetron than ramosetron complained of dull headache. 

A related group of antagonists that possess an imidazole or related heterocyclic terminal amine include ondansetron (Zofran), alosetron (Lotronex), fabesetron, and ramosetron (Fig. 14.15). Many others have been described (75,76). The SARs of 5-HT3 antagonists have been reviewed in detail elsewhere (75,76,77). 

Furthermore, delavirdine (Rescriptor) is a novel HIV-1 reverse transcriptase inhibitor for HIV-positive individuals and zafirlukast (Accolate) is an anti-asthma drug. The anti-emetics ramosetron (Nasea) and dolasetron (Anzemet) are potent and highly selective 5-HTj receptor antagonists for die treatment of chemotherapy-induced nausea and vomiting. 

In a prospective, randomized, doubleblind comparison of ramosetron or ondansetron in the management of opioid-induced postoperative nausea and vomiting, 94 patients received fentanyl 25 micrograms/kg in a total volume of 100 ml at a rate of 2 ml/hour and 0.5 ml per demand with a 15-minute lockout period [77 ]. Ramosetron was superior to ondansetron in preventing vomiting and reducing the severity of nausea. 

Choi YS, Shim JK, Yoon DH, Jeon DH, Lee JY, Kwak YL. Effect of ramosetron on patient-controlled analgesia related nausea and vomiting after spine surgery in highly susceptible patients comparison with ondansetron. Spine 2008 33(17) E602-6. 

Ondansetron versus ramosetron In a double-blind, randomized study of intravenous ramosetron 0.3 mg and ondansetron 4 mg followed by 12 mg in preventing nausea and vomiting related to opioid-based patient-controUed analgesia in 94 women... 

Ho CL, Su WC, Hsieh RK, Lin ZZ, Chao TY. A randomized, double-blind, parallel, comparative study to evaluate the efficacy and safety of ramosetron plus dexamethasone injection for the prevention of acute chemotherapy-induced nausea and vomiting. Jpn J Clin Oncol 2010 40 294-301. 

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