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PubMed1997

Nonenzymatic and enzymatic hydrolysis of alkyl halides: a theoretical study of the SN2 reactions of acetate and hydroxide ions with alkyl chlorides.

The SN2 displacements of chloride ion from CH3Cl, C2H5Cl, and C2H4Cl2 by acetate and hydroxide ions have been investigated, using ab initio molecular orbital theory at the HF/6-31+G(d), MP2/6-31+G(d), and MP4/6-31+G(d) levels of theory. The central barriers (calculated from the initial ion-molecule complex) of the reactions, the differences of the overall reaction energies, and the geometries of the transition states are compared. Essential stereochemical changes before and after the displacement reactions are described for selected cases. The gas phase reactions of hydroxide with CH3Cl, C2H5Cl, and C2H4Cl2 have no overall barrier, but there is a small overall barrier for the reactions of acetate with CH3Cl, C2H5Cl, and C2H4Cl2. A self-consistent reaction field solvation model was used to examine the SN2 reactions between methyl chloride and hydroxide ion and between 1,2-dichloroethane and acetate in solution. As expected, the reactions in polar solvent have a large barrier. However, the transition state structures determined by ab initio calculations change only slightly in the presence of a highly polar solvent as compared with the gas phase. We also calibrated the PM3 method for future study of an enzymatic SN2 displacement of halogen.

Acetates↗
PubMed2002

Randomized phase III study of fludarabine phosphate versus cyclophosphamide, vincristine, and prednisone in patients with recurrent low-grade non-Hodgkin's lymphoma previously treated with an alkylating agent or alkylator-containing regimen.

PURPOSE: To compare in a phase III study the safety and efficacy of fludarabine to that of cyclophosphamide, vincristine, and prednisone (CVP) in recurrent, low-grade, non-Hodgkin's lymphoma after previous response to systemic treatment. PATIENTS AND METHODS: Patients were randomized to fludarabine (25 mg/m(2) intravenously on days 1 to 5, every 28 days) or CVP (cyclophosphamide 750 mg/m(2) and vincristine 1.2 mg/m(2) both intravenously on day 1 and prednisone 40 mg/m(2) orally on days 1 to 5, every 21 days). The primary outcome assessed was progression-free survival (PFS); secondary outcomes included treatment-free survival (TFS), overall survival (OS), treatment-related toxicity, and quality of life (QoL) according to the European Organization for Research and Treatment of Cancer's Quality of Life Questionnaire C-30 version 1.0 instrument. RESULTS: Ninety-one patients were randomized, 47 to fludarabine and 44 to CVP. There was no difference in response rates, with 64% (complete response [CR], 9%) for fludarabine versus 52% (CR, 7%) for CVP (P =.72). With a median follow-up of 42 months, median PFS (11 months v 9.1 months; P =.03) and TFS (15 months v 11 months; P =.02) were superior in patients receiving fludarabine. No difference in median overall survival was detected (57 months for fludarabine v 44 months for CVP; P =.95). Three patients receiving fludarabine died of treatment-related toxicity compared with none of the patients receiving CVP. Peripheral neuropathy and alopecia were more common with CVP. Patients receiving fludarabine had higher scores for social function (P =.008); no other differences in QoL were detected. CONCLUSION: In recurrent low-grade lymphoma, fludarabine improves PFS, TFS, and social function scores in comparison with CVP but does not improve OS.

Adult↗
PubMed1986

Clavines as antitumor agents, 3: Cytostatic activity and structure/activity relationships of 1-alkyl agroclavines and 6-alkyl 6-noragroclavines.

The cytostatic potential of twenty antibiotic agroclavines has been examined in the L5178y mouse lymphoma cell system. Twelve of these compounds are described for the first time. It is shown that the substituent at N-1 of agroclavine is very important whereas the substituent at N-6 is of less influence if it is not hydrogen. Incorporation studies in the presence of 1-propylagroclavine suggest that DNA synthesis in the lymphoma cells is inhibited. The effect on the corresponding [3H]thymidine incorporation in murine spleen lymphocytes is comparably low. Neither a significant change of mRNA efflux nor of DNA polymerase alpha and beta activities was caused. The mechanism of action seems to be a fundamentally new one for ergoline compounds as interactions with alpha-adrenoceptors, dopamine and 5-hydroxytryptamine receptors are not involved.

Animals↗
PubMed1992

[Investigation of activity of new quaternary imidazole-linear chlorides against selected bacterial strains. Synthesis of 2-alkyl-3-alkymethyl-1-ethylimidazolelinear and 2-alkyl-3-alkoxymethyl-1-ethylimidazolelinear chlorides].

Synthesis and bacteriostatic properties of a new alkylthiomethylimidazole-linear and alkomethyly-limidazole-linear chlorides was described. It was found that these chlorides are active against bacilli, cocci and yeast-like fungi and express lower activity against rods. Highest activity was observed with 2-benzyl-3-decyloxymethyl-1--ethylimidazolinear and 1-ethyl-heptadecyl-3-undecyloxymethylimidazolelinear chlorides.

Bacteria↗