Evaluation of a chiral cubane-based Schiff base ligand in asymmetric catalysis reactions

Recently, a novel chiral cubane-based Schiff base ligand was reported to yield modest enantioselectivity in the Henry reaction. To further explore the utility of this ligand in other asymmetric organic transformations, we evaluated its stereoselectivity in cyclopropanation and Michael addition reactions. Although there was no increase in stereocontrol, upon computational evaluation using both M06L and B3LYP calculations, it was revealed that a pseudo six-membered ring exists, through H-bonding of a cubyl hydrogen to the copper core. This decreases the steric bulk above the copper center and limits the asymmetric control with this ligand.The authors thank the Niagara University Academic Center for Integrated Science and the Rochester Academy of Science for their financial support. MLI would like to thank the Barbara S. Zimmer Memorial Research Award for financial aid. MLC gratefully acknowledges generous allocations of supercomputing time from the Australian National Computational Infrastructure, support from the Australian Research Council under its Centers of Excellence program, and an ARC Future Fellowship. RP would also like to thank Western New England University, College of Pharmacy for generous financial support

Relating mechanical properties of paper to papermaking variables.

Ph.D

Effectiveness and safety of nitrofurantoin in outpatient male veterans

Objectives: The aim of the study was to assess both the safety and the effectiveness of nitrofurantoin in male veterans treated for urinary tract infections (UTIs) with varying degrees of renal impairment in the outpatient setting. Nitrofurantoin is an important oral option for treating UTIs given increasing resistance to commonly used agents. Nitrofurantoin is currently contraindicated in patients with a creatinine clearance (CrCl) of < 60 ml/min, but the reason for this threshold has not been well documented. Methods: Data were collected through a retrospective chart review from January 2004 to July 2013 of men who had received nitrofurantoin. Bivariate analyses followed by multivariate analyses were performed between patients experiencing clinical cure and those who did not, to determine factors significantly impacting effectiveness. Results: The Gram stain of the organism causing the UTI and CrCl were significant factors impacting effectiveness. For every 1 ml/min increase in CrCl, the odds of clinical cure increased by 1.3%. Patients with Gram-negative UTIs predictably had 80% cure rates with CrCl around 60 ml/min. Patients with Gram-positive UTIs required higher CrCl, nearing 100 ml/min, to establish an 80% cure rate. Adverse effects did not vary with CrCl. Conclusions: The odds of clinical cure varied with CrCl and with the type of organism causing the UTI, while adverse events did not differ based on renal function. A minimum CrCl of 60 ml/min is suggested for men to achieve an 80% cure rate for UTIs with the most common urinary pathogens

Evaluation of a chiral cubane-based Schiff base ligand in asymmetric catalysis reactions Open Access

Abstract Recently, a novel chiral cubane-based Schiff base ligand was reported to yield modest enantioselectivity in the Henry reaction. To further explore the utility of this ligand in other asymmetric organic transformations, we evaluated its stereoselectivity in cyclopropanation and Michael addition reactions. Although there was no increase in stereocontrol, upon computational evaluation using both M06L and B3LYP calculations, it was revealed that a pseudo six-membered ring exists, through H-bonding of a cubyl hydrogen to the copper core. This decreases the steric bulk above the copper center and limits the asymmetric control with this ligand. 181

Evaluation of a chiral cubane-based Schiff base ligand in asymmetric catalysis reactions

Recently, a novel chiral cubane-based Schiff base ligand was reported to yield modest enantioselectivity in the Henry reaction. To further explore the utility of this ligand in other asymmetric organic transformations, we evaluated its stereoselectivity in cyclopropanation and Michael addition reactions. Although there was no increase in stereocontrol, upon computational evaluation using both M06L and B3LYP calculations, it was revealed that a pseudo six-membered ring exists, through H-bonding of a cubyl hydrogen to the copper core. This decreases the steric bulk above the copper center and limits the asymmetric control with this ligand

Utilization of cryopreserved sperm cells based on the indication for storage

Purpose: Cryopreservation of sperm from human semen has been available since the 1950s. The actual utilization of available cryopreservation technology has been infrequently reported. We set out to examine the utilization and outcomes of cryopreserved sperm cells based on the indication for storage. Materials and Methods: A dataset was developed from retrospective review. The purposes for cryopreservation, eventual utilization, and outcomes of use for insemination were recorded. The types of utilization were accumulated as proportions for different purposes. The timing for use of samples for insemination procedures was evaluated using survival statistics. The frequency of patients arranging to destroy samples was also reported. Results: From September 1988 through March 2015, 1442 samples were cryopreserved. Samples were cryopreserved for four primary purposes: infertility treatments focused on intrauterine insemination (IUI) or in vitro fertilization/intracellular injection (IVF/ICSI), for fertility preservation related to cancer treatment, or prior to military deployment. Total utilization rates were 19.3%. Samples cryopreserved for IUI were more likely to be used (64.3%), while samples cryopreserved as backup for IVF/ICSI were more likely to be destroyed (29.8%). Pregnancy rates varied based on the indication and ART used. Pregnancies per cycle were 35% for IVF/ICSI and were 10% for IUI. Conclusions: Cryopreservation of sperm is a valuable and underutilized resource, particularly amongst male cancer patients. This technology can facilitate infertility treatments based on a variety of indications, including deployment—a patient cohort unique to our dataset