Computation of Electron Affinities of O and F Atoms, and Energy Profile of F-H2 Reaction by Density Functional Theory and Ab Initio Methods

The validity of hybrid and nonlocal DFT methods are tested on examples of systems which are difficult to model by way of quantum chemistry techniques. The electron affinities for the oxygen and fluorine atoms were calculated. The exothermicity, the barrier for the fluorine atom reaction with the hydrogen molecule, and the energy of the H–F bond and its distance were computed with DFT methods, as well as, with ROHF, MPn, and QCISD ~T! ab initio methods. The computations were performed by using various basis sets, with 6-311 11G(3d f ,3pd as the largest. The obtained results are compared with the experimental values. The results of the Becke3LYP hybrid method is in qualitative agreement with experimental results and in the majority of the cases reassembles the high cost QCISD ~T! calculation results. Considering the modest computational cost for DFTmethods, Becke3LYP/6-311 1G(2d,2p) is suggested as the standard theory model for computation, and Becke3LYP/6-311 1G(3d f ,3pd) as the model for generating highly accurate results. They should be applicable to relatively sizable chemical systems

Computation of Electron Affinities of O and F Atoms, and Energy Profile of F-H2 Reaction by Density Functional Theory and Ab Initio Methods

The validity of hybrid and nonlocal DFT methods are tested on examples of systems which are difficult to model by way of quantum chemistry techniques. The electron affinities for the oxygen and fluorine atoms were calculated. The exothermicity, the barrier for the fluorine atom reaction with the hydrogen molecule, and the energy of the H–F bond and its distance were computed with DFT methods, as well as, with ROHF, MPn, and QCISD ~T! ab initio methods. The computations were performed by using various basis sets, with 6-311 11G(3d f ,3pd as the largest. The obtained results are compared with the experimental values. The results of the Becke3LYP hybrid method is in qualitative agreement with experimental results and in the majority of the cases reassembles the high cost QCISD ~T! calculation results. Considering the modest computational cost for DFTmethods, Becke3LYP/6-311 1G(2d,2p) is suggested as the standard theory model for computation, and Becke3LYP/6-311 1G(3d f ,3pd) as the model for generating highly accurate results. They should be applicable to relatively sizable chemical systems

New Approaches in the Treatment of Glioblastoma Multiforme

Central nervous system (CNS) malignancies are rare, but commonly fatal and glioblastoma (GBM) is the most common of the primary brain tumors. In contrast to metastatic malignancies involving the CNS, which have external blood supplies that develop when the malignant cells penetrate the blood-brain-barrier (BBB), GBM generates its own intracerebral neovascular support system. Thus, the therapeutic issues as discussed herein review the development of drugs and therapeutics that will penetrate the BBB and are cytotoxic to GBM and other brain tumors. Since GBM is a CNS malignancy with minimal effective therapeutic options available, designing drugs and therapeutics as treatment for this malignancy that penetrate, but do not disrupt the BBB is the goal of this chapter. 4-Demethylcholesteryl-4-penclomedine (DM-CHOC-PEN) was designed and developed because of its lipophilic properties that would potentiate crossing the BBB and penetrate brain tumors. The drug has now completed Phase I/II clinical trial in humans with primary brain malignancies demonstrating objective responses in GBM. In addition, preliminary experiences with naturally occurring polyphenols—curcumin, quercetin, catechins and phloretin and derivatives—are reviewed as potential naturally occurring anti-glioblastoma agents

Comparative Anticancer Activity in Human Tumor Xenograft Models, Preclinical Pharmacology and Toxicology for 4- Hydroperoxyifosfamide (HOOI): A Potential Neuro-Alkylating Agent for Primary and Metastatic Cancers Involving the Central Nervous System

Background: 4-Hydropeoxyifosfamide (HOOI) is a hydroperoxy derivative of ifosfamide that was developed as an anticancer agent that can penetrate the blood-brain barrier (BBB), which can be potentially useful in the management of brain tumors