Besylate

Chemical Name 10-[2-(1-methvl-2-piperidinvl)ethyl] -2-methylsulfinyl-10H-phenothiazine benzene sulfonate 

Acetic anhydride Potassium carbonate Sodium hydroxide 

0 g of 3-methylmercapto phenothiazine and 17.5 cc of acetic acid anhydride are refluxed for 8 hours from an oil bath maintained at a temperature of 180°C. After concentration of the solution the residue is crystallized from ethanol. The pure 3-methylmercapto-10-acetyl phenothiazine melts at 89° to 91°C. For the purpose of oxidation 5.0 g of 3-methylmercapto-10-acetyl phenothiazine are dissolved in 50 cc of ethanol, refluxed from an oil bath maintained at 120°C and 1.6 cc of a 40% hydrogen peroxide solution are then added dropwise in the course of 30 minutes. 

Heating is continued for another 5 hours and the reaction mixture is concentrated after 50 cc of water have been added. The residue is taken up in 40 cc of benzene and the benzene layer washed with 10 cc of water. After having been concentrated, the residue, crude S-methylsulfinyl-IO-acetyl phenothiazine, is dissolved in 55 cc of a 90% methanol solution for splitting off the acetyl group and, after 2.9 g of potassium carbonate have been added, it is boiled for 2 hours under reflux on an oil bath kept at a temperature of 120°C. After concentration, the residue Is taken up in 50 cc of chloroform, the chloroform layer Is washed with a total of 25 cc of water, dried over potassium carbonate, filtered and concentrated. After twice crystallizing the residue, each time from 50 cc of ethanol, analytically pure 3-methylsulfinyl phenothiazine (MP 193° to 195°C) is obtained. 

A mixture of 10.0 g of 3-methylsulfinyl phenothiazine (MP 193° to 195°C), 6.1 g of finely powdered sodium hydroxide and 125 cc of toluene is boiled for 1 hour under reflux with a water separator on an oil bath kept at a temperature of 150°C, while the mixture is stirred. Without interrupting the boil a solution of 7.0 g of 2-(N-methvl-piperidyl-2 )-1-chloroethane (BP 84°C/10 mm Hg) in 10 cc of toluene is added dropwise in the course of 1 hour, after which boiling is continued for another 3 hours. When the reaction mixture has cooled it is first washed with 25 cc of water three times and then extracted with 75 cc of a 15% aqueous tartaric acid solution. The tartaric acid extract is shaken out with 25 cc 

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After having been washed with 50 cc of water the benzene layer is dried over potassium carbonate, filtered, allowed to stand over 10 g of alumina for about VA hours for partial decolorization, filtered again and concentrated under reduced pressure. The oily base which remains as a residue is directly converted into the tartrate. A solution cooled to 0°C, of 6.50 g of the free base in 100 cc of acetic acid ethyl ester is thoroughly shaken and poured into an ice cold solution of 2.66 g of tartaric acid in 410 cc of acetic acid ethyl ester. The precipitated, analytically pure, tartrate of 3-methylsulfinyl-10-[2 -N-methyl-piperidyl-2")-ethyl-1 ]-phenothiazine melts at 115° to 120°C (foam formation) and sinters above B0°C. The base Is reacted with benzene sulfonic acid in a suitable solvent to give the besylate. 

Mesoridazine besylate Methoqualone Metoclopramide HCI Metolazone Midazolam maleate Moxisylyte Nadolol Naloxone... 

CjHjBrO, 590-92-1) see Cisatracurium besylate 2-bromopropionitrile (CjH4BrN 19481-82-4) see Lofexidine 2-bromopropionyl bromide... 

C20H25NO4 73074-37-2) see Atracurium besilate (/t)-tetrabydropapaverine 7V-acetyl-L-leucinate (C2gH4(,N207 141109-12-8) see Cisatracurium besylate ( )-tetrabydropapaverine bydrocbloride (C20H26CINO4 6429-04-5) see Cisatracurium besylate [ -( , 5 )]-2,3,4,9-tetrabydro-7V-(l-phenylethyt)-lff-carbazol-3-amine sulfate (1 1)... 

Online detection using 4H nuclear magnetic resonance (NMR) is a detection mode that has become increasingly practical. In a recent application, cell culture supernatant was monitored on-line with 1-dimensional NMR for trehalose, P-D-pyranose, P-D-furanose, succinate, acetate and uridine.33 In stopped-flow mode, column fractions can also be analyzed by 2-D NMR. Reaction products of the preparation of the neuromuscular blocking compound atracurium besylate were separated on chiral HPLC and detected by 4H NMR.34 Ten isomeric peaks were separated on a cellulose-based phase and identified by online NMR in stopped-flow mode. 

Mistry, N., Roberts, A.D., Tranter, G.E., Francis, P., Barylski, I., Ismail, I.M., Nicholson, J.K., and Lindon, J.C., Directly coupled chiral HPLC-NMR and HPLC-CP spectroscopy as complementary methods for structural and enantiomeric isomer identification application to atracurium besylate, Anal. Chem., 71, 2838, 1999. 

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