Methotrimeprazine, chemical structure, molecular formula, Reference Standards

Methotrimeprazine

C19H24N2OS 328.47

10H-Phenothiazine-10-propanamine,2-methoxy-N,N,b-trimethyl-,(-)-.
(-)-10-[3-(Dimethylamino)-2-methylpropyl]-2-methoxyphenothiazine [60-99-1].

»Methotrimeprazine contains not less than 98.0percent and not more than 101.0percent of C19H24N2OS,calculated on the dried basis.

Packaging and storage— Preserve in well-closed,light-resistant containers.Store at 25

,excursions permitted between 15

and 30

USP Reference standards á11ñ— USP Methotrimeprazine RS.

NOTE—Throughout the following procedures,protect test or assay specimens,the USP Reference Standard,and the solutions containing them,by conducting the procedures without delay,under subdued light,or using low-actinic glassware.

Identification—

A:Infrared Absorption á197Kñ.

B:Ultraviolet Absorption á197Uñ—

Solution: 7µg per mL.

Medium: alcohol.Absorptivities at 255nm,calculated on the dried basis,do not differ by more than 3.0%.

Specific rotation á781Sñ: between -15

and -18

Test solution: 50mg per mL,in chloroform.

Loss on drying á731ñ— Dry it at 100

for 3hours:it loses not more than 0.5%of its weight.

Selenium á291ñ— The absorbance of the solution from the Test Solution,prepared with 100mg of Methotrimeprazine and 100mg of magnesium oxide,is not greater than one-half that from the Standard Solution(0.003%).

Assay— Dissolve about 700mg of Methotrimeprazine,accurately weighed,in 100mLof chloroform,add 1drop of a 1in 500solution of crystal violet in chloroform,and titrate with 0.1Nperchloric acid VSto the first disappearance of the violet tinge.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 32.85mg of C19H24N2OS.

Auxiliary Information— Staff Liaison:Daniel K.Bempong,Ph.D.,Scientist

Expert Committee:(PA2)Pharmaceutical Analysis 2

USP28–NF23Page 1250

Pharmacopeial Forum:Volume No.29(6)Page 1931

Phone Number:1-301-816-8143