Land Use Change Increases Wildlife Parasite Diversity in Anamalai Hills, Western Ghats, India.

Anthropogenic landscape changes such as land use change and habitat fragmentation are known to alter wildlife diversity. Since host and parasite diversities are strongly connected, landscape changes are also likely to change wildlife parasite diversity with implication for wildlife health. However, research linking anthropogenic landscape change and wildlife parasite diversity is limited, especially comparing effects of land use change and habitat fragmentation, which often cooccur but may affect parasite diversity substantially differently.

Physiological stress responses of tigers due to anthropogenic disturbance especially tourism in two central Indian tiger reserves.

Tigers continue to face unprecedented threats to their existence due to poaching, habitat loss, habitat fragmentation and anthropogenic disturbances. The present study examines the physiological stress response of tigers due to anthropogenic activities including wildlife tourism in Bandhavgarh Tiger Reserve and Kanha Tiger Reserve using faecal glucocorticoid metabolite (fGCM) measurement. We collected a total of 341 faecal samples from both reserves during tourism and non-tourism periods.

Simple Enantioselective Syntheses of (2R,6R)-Hydroxynorketamine and Related Potential Rapid-Onset Antidepressants.

A novel strategy for accessing cyclic α-amino ketones enantioselectively has opened a simple synthetic route to the antidepressant (2R,6R)-hydroxynorketamine and numerous analogues. Mechanistically guided catalyst selection was essential in an initial olefin epoxidation step. In a second crucial step, the epoxide was subjected to a novel O → N displacement that occurred with retention of configuration through the use of Al- or Ti-based azides, which promote epoxide activation and internal cis delivery of N to carbon.

Useful Applications of Enantioselective (4 + 2)-Cycloaddition Reactions to the Synthesis of Chiral 1,2-Amino Alcohols, 1,2-Diamines, and β-Amino Acids.

The scope of enantioselective (4 + 2)-cycloaddition reactions has been expanded to include reactive olefinic components that are equivalents of three inoperable and unstable ethylene derivatives: 1-hydroxy-2-aminoethylene, 1,2-diaminoethylene, and β-aminoacrylic acid. In this way, a variety of otherwise unavailable functionalized (4 + 2)-cycloadducts have been synthesized from 1,3-dienes with high enantioselectivity (92-98%) and in good yields. The research leading up to this synthetic advance has also produced some surprising insights on reactivity and positional selectivity in catalytic enantioselective (4 + 2)-cycloaddition.

Acceleration of Enantioselective Cycloadditions Catalyzed by Second-Generation Chiral Oxazaborolidinium Triflimidates by Biscoordinating Lewis Acids.

The activation of second-generation fluorinated oxazaborolidines by the strong acid triflimide (Tf2NH) in CH2Cl2 solution leads to highly active chiral Lewis acids that are very effective catalysts for (4 + 2) cycloaddition. We report herein that this catalytic activity can be further enhanced by the use of Tf2NH in combination with the biscoordinating Lewis acid TiCl4 or SnCl4 as a coactivator. The effective increase in acidity of an exceedingly strong protic acid is greater for biscoordinating TiCl4 and SnCl4 than for monocoordinating salts, even the strong Lewis acids AlBr3 and BBr3 in CH2Cl2 or CH2Cl2/toluene.

Prevalence of Gastrointestinal Parasites in Civets of Fragmented Rainforest Patches in Anamalai Hills, Western Ghats, India.

:  Parasitism, driven by anthropogenic habitat modifications, is being increasingly recognized as a major threat to wildlife. Unfortunately, even baseline parasite data for most wildlife species are lacking in India, including the civets, which are particularly vulnerable due to their proximity to human habitations. Civet fecal samples were collected from 10 forest fragments that vary in size and disturbance level in Anamalai Hills, Western Ghats, India.

Cationic Chiral Fluorinated Oxazaborolidines. More Potent, Second-Generation Catalysts for Highly Enantioselective Cycloaddition Reactions.

The coordination of chiral ligands to Lewis acid metal derivatives, a useful strategy for enantioselective, electrophilic catalysis, generally leads to a lower level of catalytic activity than that of the original uncomplexed compound. Activation by further attachment of a proton or strong Lewis acid to the complex provides a way to overcome the deactivating effect of a chiral ligand. The research described herein has demonstrated that further enhancement of catalytic activity is possible by the judicious placement of fluorine substituents in the chiral ligand.

A concise approach for the synthesis of bitungolides: total syntheses of (-)-bitungolide B & E.

The first total synthesis of (-)-bitungolide B and a second-generation total synthesis of (-)-bitungolide E are described. The cornerstone of the approach comprises a convergent and flexible route involving Brown crotylation, highly diastereoselective substrate controlled Paterson anti-aldol reaction, hydroxyl-directed 1,3-syn/anti reduction, Barton-McCombie deoxygenation and RCM reactions. Via this route, a common intermediate 13 is readily accessible for the synthesis of the family of bitungolides A-E and franklinolides A-C.