Study of polymorphism in imatinib mesylate: a quantum chemical approach using electronic and vibrational spectra

Imatinib mesylate, 4-(4-methyl-piperazin-1-ylmethyl)-N-u[4-methyl-3-(4-pyridin-3-yl)pyrimidine-2-ylamino)phenyl]benzamide methanesulfonate is a therapeutic drug that is approved for the treatment of chronic myelogeneous leukemia (CML) and gastrointestinal stromal tumors (GIST). It is known that imatinib mesylate exists in two polymorphic forms α and β. However, β-form is more stable than the α-form. In this work, we present a detailed vibrational spectroscopic investigation of β-form by using FT-IR and FT-Raman spectra. These data are supported by quantum mechanical calculations using DFT employing 6-311G(d,p) basis set, which allow us to characterize completely the vibrational spectra of this compound. The FT-IR spectrum of α-form has also been discussed. The importance of hydrogen-bond formation in the molecular packing arrangements of both forms has been examined with the vibrational shifts observed due to polymorphic changes. The red shift of the NH stretching bands in the infrared spectrum from the computed wavenumber indicates the weakening of the NH bond. The UV-vis spectroscopic studies along with the HOMO-LUMO analysis of both polymorphs (α and β) were performed and their chemical activity has been discussed. The TD-DFT method was used to calculate the electronic absorption spectra in the gas phase as well as in the solvent environment using IEF-PCM model and 6-31G basis set. Finally, the results obtained complements to the experimental findings.

A chronic disease prevention program

In a pilot chronic disease prevention program at the Hinds County Health Department in Jackson, Mississippi, 1030 patients were evaluated with yearly complete physical evaluation, Pap Smears, screening mammography, and other appropriate tests and procedures. The patients were also provided with nutritional and healthy lifestyle education. The study lasted for 3 1/2 years. It was done in conjunction with a pre-existing hypertension program. Although the benefits of the educational effort were more intangible in the relatively short period of time of the study, it is significant that mammography identified eight (8) occult breast cancers. We believe this pilot study only touches the surface of what could be done with more extensive preventive measures.

Mangement of dyspareunia secondary to hymenal remnants

At the Sexual Dysfunction Clinic at Keesler USAF Medical Center, 17 women complaining of dyspareunia with painful hymen and demonstrable vaginismus were managed by surgical removal of hymenal remnants followed by directive sexual therapy and progressive vaginal dilatation. All patients were pain free within 8 weeks of the surgical procedures. It is believed that a combined approach is best to break the cycle of pain, fear, vaginismus, and more pain that these women have established.

The effect of oral contraceptive steroids on branches of the uterine artery

Uteri from 38 patients exposed to oral contraceptive steroids and from 7 unexposed controls were examined for lesions in small branches of the uterine artery. Moderate or severe cellular proliferation of the intimal layer was found in 82% of patients exposed to exogenous steroids, but minimal or no involvement was found in the remaining 18% and in unexposed patients. The severity of involvement correlated with duration of exposure to contraceptive steroids but decreased in those patients who had stopped medication prior to surgery. This lesion has been reported previously in autopsy studies of women receiving contraceptive steroids and dying from vascular disease, but is now shown to be common in asymptomatic women receiving oral contraceptive pills.