2-Amino-2',5-dichlorobenzophenone

Conformations of substituted benzophenones.[Pubmed:18369292]

Acta Crystallogr B. 2008 Apr;64(Pt 2):206-16.

The inclination of the two aryl rings (ring twists) in a series of benzophenone molecules has been examined. For each structure the dihedral angle (between the planes of the two sets of six aromatic C atoms) relates to both the steric considerations of the single molecule and the packing forces related to the crystal structure. Six new benzophenone structures are incorporated into the study including 2,2'-dihydroxy-4,4'-dimethoxybenzophenone (I), C(15)H(14)O(5), that appears to have the smallest reported twist angle, 37.85 (5) degrees , of any substituted benzophenone reported to date. Three further benzophenones, 4,4'-bis(diethylamino)benzophenone (II), C(21)H(28)N(2)O, 3,4-dihydroxybenzophenone (III), C(13)H(10)O(3), and 3-hydroxybenzophenone (IV), C(13)H(10)O(2), have similar ring twists [49.83 (5), 49.84 (5) and 51.61 (5) degrees , respectively] that are comparable with the value of 54 degrees found for the orthorhombic form of unsubstituted benzophenone. 4-Chloro-4'-hydroxybenzophenone (V), C(13)H(9)ClO(2), has a ring twist of 64.66 (8) degrees that is close to the value of 65 degrees found in the metastable monoclinic form of unsubstituted benzophenone and 2-amino-2',5-dichlorobenzophenone (VI), C(13)H(9)Cl(2)NO(2), has a large ring twist of 83.72 (6) degrees . Comparisons with a further 98 substituted benzophenone molecules from the Cambridge Structural Database (CSD) have been made.

[Detection of lorazepam and lormetazepam metabolites in urine using thin-layer chromatography].[Pubmed:9560883]

Soud Lek. 1998 Jan;43(1):2-4.

The determination of benzodiazepine derivatives lorazepam and lormetazepam in urine is based on detection of their metabolites 2-amino-2',5-dichlorobenzophenone and 2-methylamino-2'5-dichlorbenzophenone in hydrolyzed urine. Both substances are structurally very similar to the metabolites of diazepam 2-amino-5-chlorbenzophenone and 2-methylamino-5-chlorbenzophenone and their mobility on thin layer chromatograms is similar as well. This could cause their confusion and misinterpretation of the results. Therefore suitable combination of mobile phases and thin layer plates was sought in this study for the unambiguous identification of respective benzophenones by thin layer chromatography.

Separation and determination of aminohalogenbenzophenones by high-performance liquid chromatography with electrochemical detection.[Pubmed:1400781]

J Chromatogr. 1992 Jul 1;578(1):146-51.

A high-performance liquid chromatographic method with electrochemical detection has been developed for the determination of three aminohalogenbenzophenones: 2-amino-2',5-dichlorobenzophenone, 2-amino-5-chlorobenzophenone and 2-amino-5-bromo-2'-fluorobenzophenone, metabolites of benzodiazepinooxazoles and other psychotropic drugs. A mobile phase of methanol-water (65:35), containing 5 mM KH2PO4 appeared to be the optimal when a 4-microns, 60-A Nova-Pak C18 column and a flow-rate of 0.75 ml/min (130 bar) were used. The temperature was optimized at 30 degrees C. The amperometric detector, equipped with glassy carbon electrode, was operated at 1.3 V versus Ag/AgCl in the DC mode. The method was applied to the determination of these compounds at two concentration levels: ppm and ppb (ng/cm3) using 2-amino-5-chlorobenzophenone as internal standard. The limit of determination was 750 pg/ml of biological fluid for each compound, and recoveries greater than 97% were obtained for spiked samples of urine and serum, using C18 Sep-Pak cartridges in the sample clean-up procedure.