Chlorpromazine, sulfoxidation

Chlorpromazine sulfoxide can be determined in the presence of chlorpromazine using cathodic polargraphy [149]. Since the bromination products of these compounds are indistinguishable, the total chlorpromazine and sulfoxide content in a sample can be determined by reductive polarography after bromination. 

Thio Ethers. Thio ethers are commonly oxidized to a sulfoxide or sulfone. The conversion of chlorpromazine to chlorpromazine sulfoxide is a good example of this. 

A spin-trapping investigation of chlorpromazine sulfoxide (CPZSO), a chlorpromazine metabolite formed in man and several other mammalian species, showed that when irradiated with near-UV light, the excited sulfoxide does not dechlorinate. Instead it produces large amounts of the highly reactive hydroxyl radical ( OH) as well as the cation radical (CPZ +) [54], The following mechanism is proposed ... 

Molnar et al. [69] studied antibacterial effect and plasmid curing property of several phenothaizines and tried to correlate these functions with respect to their chemical structure. They observed that diethazine, amitriptyline, and impipramine showed bacteriostatic and bactericidal effect on different bacteria. Chlorpromazine sulfoxide and fluorescein were ineffective even at 1000 Ag/ml. The antibacterial compounds deleted at 40-70% frequency the F lac-t- plasmid of Escherichia coli K12 Le-140. Similar plasmid elimination potentiality by phenothiazines was reported by the same group of authors in 1982 [72],... 

Enzymatic in vitro oxidation of chlorpromazine to chlorpromazine sulfoxide via the free radical and the phenazathionium cation has been reported. ... 

Sometimes drugs and their metabolites are extractable into the same solvents. For example, chlorpromazine, demonomethylchlorpromazine, dedrmethylchlorproma-zine, and chlorpromazine sulfoxide are extractable into heptane.f However, adjustment of the pH of the aqueous medium to various values between 4 and 11 permits selective extraction of one or another of the compounds. An example of the application of this principle is that chlorpromazine analysis utilizes a pH 4.6 backwash, which leaves most of the chlorpromazine in... 

The first step of the photodegradation is the loss of an electron to yield the semiquinone free radical R. Further stages in the degradation yield the phenazathonium ion P, which is thought to react with water to yield chlorpromazine sulfoxide (CPO). The chlorpromazine sulfoxide is itself photolabile and further decomposition occurs. Other products of the photooxidation include chlorpromazine N-oxide and hydroxychlorpromazine. 

Just as in ultraviolet-visible spectrophotometry, derivative techniques have also been applied to the analysis of fluorescent substances in multicomponent preparations. The advantages here are reported to be the enhanced spectral resolution and amplification of signal that manifests with substances exhibiting narrower spectral bands. Derivative spectrofluorimetric techniques have been applied, for example, to the determination of chlorpromazine sulfoxide in chlorpromazine hydrochloride preparations. 

Buettner, G.R., Motten, A.G., Hall, R.D., and Chignell, C.F. (1986) Free radical production by chlorpromazine sulfoxide, an ESR spin-trapping and flash photolysis study, Photo-chem. Photobiol., 44, 5-10. 

It may be noted in Figure 13 that the chlorpromazine cation radical reacts at physiological pH to give other products. Tozer and co-workers " " observed that the cation radical hydrolyzes in aqueous solution to yield chlorpromazine and chlorpromazine sulfoxide in a roughly second-order reaction. Thus, these authors proposed a disproportionation mechanism although it was based on a rather incomplete kinetic analysis. Subsequent studies " have revealed that in phosphate and citrate media, 1 mol of chlorpromazine cation... 

Chlorpromazine sulfoxide, a chlorpromazine metabolite formed in man and several other mammalian species, produced when irradiated with near-UV light large amounts of the highly reactive hydroxyl radical (Buettner et al. 1986). 

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