Timolol maleate

Kawaru, M., Kanno, T., Saito, S. and Tamaki, H., assigned to Tanabe Seiyaku Co., Ltd. (Japan) 

Chemical Name S-(-)-1 -tert-butylamino)-3-[(4-morpholino-1,2,5-thiadiarol-3-yl)oxy] -2-propanol maleate 

Trade Name Manufacturer Country Year Introduced 

Step A Preparation of 3-tert-Butylamino-2-Oxopropanoi — To an aqueous solution of tert-butylamine (1 mol) at ambient temperature, there is added slowly and with vigorous stirring 2 mols bromoacetol. The reaction mixture is allowed to stand at ambient temperature for about 5 hours whereupon it is made basic by the addition of sodium hydroxide. 

The reaction mixture then is extracted with ether, the excess amine is removed from the ethereal solution under reduced pressure and the ether then removed by evaporation to give 3-tert-butylamino-2-oxopropanol. 

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Timolol maleate a-Bromoacetophenone Nomifensine maleate Bromoacetyl bromide Bromazepam Cephapirin sodium Clonazepam Flunitrazepam 5-Bromoacetyl salicylamide Labetalol HCI m-Bromoanisole Tramadol HCI p-Bromoanisole Cyclofenil Bromobenzene... 

Tenoretic—chlortlialidone, atenolol Timolide—hydrochlorotliiazide, timolol maleate T ri-Hydroserpine—hydrochlorothiazide, reserpine,... 

Co-administration of ofloxacin and chitosan in eyedrops increased the bioavailabUity of the antibiotic [290]. Trimethyl chitosan was more effective because of its solubility (plain chitosan precipitates at the pH of the tear fluid). On the other hand, N-carboxymethyl chitosan did not enhance the corneal permeability nevertheless it mediated zero-order ofloxacin absorption, leading to a time-constant effective antibiotic concentration [291]. Also W,0-carboxymethyl chitosan is suitable as an excipient in ophthalmic formulations to improve the retention and the bioavailability of drugs such as pilocarpine, timolol maleate, neomycin sulfate, and ephedrine. Most of the drugs are sensitive to pH, and the composition should have an acidic pH, to enhance stability of the drug. The delivery should be made through an anion exchange resin that adjusts the pH at around 7 [292]. Chitosan solutions do not lend themselves to thermal sterilization. A chitosan suspension, however. 

TIMOLOL MALEATE OPHTHALMIC SOLUTION USP 5ML BOTTLE WITH TIP 6505010696519 BT 3.20 ... 

Marini, R. D., Rozet, E., Vander Heyden, Y., Boulanger, B., Bouklouze, A., Servais, A.-C., Fillet, M., Crommen, J., and Hubert, Ph. (2007). Robustness testing of a chiral NACE method for R-timolol determination in S-timolol maleate and uncertainty assessment from quantitative data. J. Pharm. Biomed. Anal. 44, 640—651. 

If an enantiomer is chemically pure it is possible to determine its degree of enantiomeric purity by measuring its optical rotation relative to a standard value, e.g if an enantiomeric mixture contains 1% of enantiomer A and 99% of enantiomer B [a] will be reduced by 2% compared to the value for optically pure B. Examples of the measurement of optical rotation as a quality control check are found in the BP monographs for Timolol maleate, Tobramycin and Phenylephrine Hydrochloride. 

Opfitfialmic Solution-. 2% dorzolamide hydrochloride and 0.5% timolol maleate (Cosopt). 

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