Oxytetracycline dihydrate

Two identification tests for oxytetracycline hydrochloride are given in the USP 28 [1], one being an ultraviolet absorption test and the other a color test. European Pharmacopoeia [2], British Pharmacopoeia (BP) 2003 [4], International Pharmacopoeia [5], and Pharmacopoeia of the People s Republic of China [6] described a thin-layer chromatography and color tests for identification of oxytetracycline hydrochloride and oxytetracycline dihydrate. For identification of oxytetracycline calcium, USP 28 [1] used Method II under identification of tetracycline <193>, whilst BP 2003 [4] described a TLC, color test, and calcium test as the method of identification. 

A light to deep red color is produced when oxytetracycline hydrochloride, oxytetracycline dihydrate, or oxytetracycline calcium is dissolved in sulfuric acid [1-5], and the color becomes yellow after water is added to the solution [1,2,4-7]. 

Any opalescence in the solution of 10 mg test substance (oxytetracycline dihydrate) in a mixture of 1 mL of dilute nitric acid R and 5 mL of water R added with 1 mL of silver nitrate solution R2 is not more intense than that in a mixture of 1 mL of dilute nitric acid R, 5 mL of a 21 mg/L solution of potassium chloride R and 1 mL of silver nitrate solution R2 [1,2]. 

The light-absorbing impurities of oxytetracycline hydrochloride and oxytetracycline dihydrate [2,4,6] are detected using a UV-spectrophotometric method. In all the compendia, the absorbance of a solution of 2.0 mg/mL in a mixture of 1 volume of hydrochloric acid solution (0.1 mol/L) and 99 volumes of methanol at 430 nm not greater than 0.50 is required the absorbance of a solution of 10 mg/mL in the same solvent at 490 nm is not greater than 0.20. The measurements are carried out within 1 h of the preparation of the solutions. 

Tetracycline and several related antibiotics (aureomycin = chlorotetracycline, terramycin — oxytetracycline dihydrate) are also obtained from various species of Streptomyces, but are of very different structure, being based on the fused polycyclic arene naphthacene. The presence of five hydroxy substituents (six for terramycin) and an NMe2 group, and possibilities for various conformations and tautomers, complicate the study of their... 

Oxytetracycline Dihydrate Triamcinolone Hexacetonide 604.3 Fazadinium Bromide... 

Drugs of the tetraeycline group are amphoteric, forming salts with both acids and bases. They are used as parent compounds (e.g., oxytetracycline dihydrate) or as salts (e.g., oxytetracycline hydrochloride). Their lipid solubilities range from moderate (oxytetracycline and chlortetracycline) to high (doxycycline and minocycline), so that they are able to traverse cell membranes moderately or readily. The former two drugs are natural tetracyclines, while the latter two are semi-synthetic. 

C22H28N2O11, Oxytetracycline dihydrate, 42B, 388 C2 2H2 sB N20i 1, Oxytetracycline hydrobromide dihydrate, 42B, 144 C22H3uIN03, (R)-N-(2-(2-Cyclohexylmandeloyloxy)ethyl)-N-methylpi-peridinium iodide, 43B, 312... 

The tetracyclines are a group of drugs which form soluble complexes with typical hydrotropes. Oxytetracycline dihydrate and tetracycline dihydrate complex with sodium salicylate, sodium saccharin, sodium p-aminobenzoate, and N-methylpyrrolidone [313] which is hardly surprising considering the polar, multifunctional character of the drugs ... 

OXYTETRACYCLINE DIHYDRATE, C22H2409N2,2H20, Mol Wt. 496-5 and OXYTETRACYCLINE HYDROCHLORIDE, C22H2409N2,HC1, Mol. Wt. 496 9 (Terramycin). 

Dissolve 20 mg in sufficient B,P. solution of standard pH 2-0 to produce 100 ml. Dilute 10 ml to 100 ml with the buffer solution and measure the extinction of the resulting solution at the maximum at about 353 mju, using 1-cm cells. E(1 per cent, 1 cm) of oxytetracycline dihydrate or oxytetracycline hydrochloride at 353 mju is 284. 

Coupling magnitudes for oxytetracycline base (dihydrate) in pyridine-ds are quite different from those seen in the spectrum of the hydrochloride salt, a fact which indicates that the base and protonated base conformations differ in a radical manner. The most striking difference is between the 4-H signals ... 

Terra Aiba 1, Terra Aiba F P, Terra alba Terra Aiba. See Calcium sulfate dihydrate Terracur P. See Fensulfothion Terra-Dry Freeze Dried Aioe Vera Powd. 100X. See Aloe barbadensis gel Terra japonica. See Black catechu Terramycin hydrochloride. See Oxytetracycline hydrochloride... 

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