Syntheses of Ketamine and Related Analogues: A Mini Review

Ketamine [2-(2-chlorophenyl)-2-(methylamino)cyclohexanone] is a dissociative anaesthetic, first developed in 1963 by Parke-Davis. It finds widespread application in the treatment of battlefield injuries, and in emergency departments for use in children. In recent times the clinical interest in ketamine has increased due to the positive impact it has in treating depression and the rapid onset of its antidepressant effect. This review covers the synthetic effort towards ketamine and related analogues over the past 60 years to give readers an overview of past, current, and future research outlook pertaining to ketamine-like molecules.1 Introduction2 Early Work3 Synthesis3.1 Ketamine3.2 Norketamine3.3 Ketamine Analogues4 Future Outlook and Conclusion

Enantioselective synthesis of structurally intricate and complementary polyoxygenated building blocks of Spongistatin 1 (Altohyrtin A)

Enantioselective approaches to the construction of four complex building blocks of the structurally intricate marine macrolide known as spongistatin 1 are presented. The first phase of the synthetic effort relies on a practical approach to a desymmetrized, enantiomerically pure spiroketal ring system incorporating rings A and B. Concurrently, the C17–C28 subunit, which houses one-fifth of the stereogenic centers of the target in the form of rings C and D, was assembled via a composite of stereocontrolled aldol condensations. Once arrival at the entire C1–C28 sector had been realized, routes were devised to provide two additional highly functionalized sectors consisting of C29–C44 and C38–C51. A series of subsequent transformations including cyclization of the E ring and hydroboration to afford the B-alkyl intermediate for the key Suzuki coupling to append the side chain took advantage of efficient stereocontrol. Ultimately, complete assembly and functionalization of the western EF sector of spongistatin was thwarted by an inoperative Suzuki coupling step intended to join the side chain to the C29–C44 sector, and later because of complications due to protecting groups, which precluded the complete elaboration of the late stage C29–C51 intermediate.

Supramolecular Assemblies for Second Order Nonlinear Optics Stabilized by Electrostatic Interaction

Electrostatic interactions are being used instead of covalent linkage to stabilize orientational order in novel materials for second order nonlinear optics. In complex supramolecular architectures, this simplifies the variation of chromophores or polymeric backbones. Other molecules can readily be inserted into the system in order to tune optical or thermodynamic properties without synthetic effort. Noncentrosymmetric ultrathin films consisting of highly ordered "active-passive" AB-Y-type multilayers of NLO active ionic amphiphiles and an ionic polymeric buffer material have been obtained by the Langmuir-Blodgett-Kuhn (LBK) technique. Combination with self-assembly by adsorption from solution is demonstrated.