In this study, we synthesized two novel carboxylic acid and carboxylate compounds, both of which had an amide group linked with an azomethine moiety to introduce photoinduced switching of the intramolecular NH...O hydrogen bond. We suggest that the cis-carboxylate compound forms a stronger intramolecular NH...O hydrogen bond than the cis-carboxylic acid compound.

A concise synthetic strategy has been developed for the synthesis of the macrolactone core 2 of a unique polyketide callyspongiolide 1. The key features of the strategy included an Evan's asymmetric alkylation, diastereoselective Michael type alkylation, Brown's asymmetric allylation reaction, an allylic alkylation of an activated Z-allylic alcohol and an intramolecular Z-selective intramolecul...

Fused cyclobutanes are found in a range of natural products and formation of these motifs in a straightforward and easy manner represents an interesting synthetic challenge. To this end we investigated an intramolecular variant of the thermal enamine [2 + 2] cyclisation, developing a diastereoselective intramolecular enamine [2 + 2] cyclisation furnishing δ lactone and lactam fused cyclobutenes...

The preparation of the diastereomerically pure beta-tetralone ketal 4 is reported. Intramolecular alkylidene C-H insertion followed by hydrolysis of 4 proceeded to give the enantiomerically pure cyclopentene 15. The key step in this synthesis was the bis-intramolecular cyclization of keto aldehyde 2 to give the tetracyclic intermediate 20. Enone 20 was converted over several steps to (-)-morphi...

An expedient synthetic route for 3-aryl beta-carbolin-1-ones was developed starting from ethyl acetamidocyanoacetate and chalcone derivatives. The five- and six-membered nitrogen-containing rings in the beta-carbolin-1-ones were elaborated efficiently by an intramolecular ketone-nitrile annulation and an intramolecular N-arylation of amide respectively.

A specific form of the inertial law is presented by which we can gain a deeper insight into the essence of mass and inertia. In this modified theory, there is no need to keep the concept of absolute space and Newton's third law as principles, By introducing a convenient form for gravitational law the coupling constant G becomes a function of inertial parameters of the universe

The previously developed theory for treating the kinematics of polymers in dense media (Bahar, I.; Erman, B.; Monnerie, L. Macromolecules 1992, 25, 6309, 6315) is extended to include the influence of internal conformational energy barriers on the mechanism of motion. The method is based on the solution of a constrained equation of motion in the presence of dissipative forces due to friction. Su...

In this paper we consider a theory for intramolecular radiationless transitions in an isolated molecule. The Bom-oppenheimer zero-order excited states are not pure in view of configuration interaction between nearly degenerate zero-order states, leading to the broadening of the excited state, the line shape being Lorentzian. The optically excited state can be described in terms of a superpositi...

The first total syntheses of spirobacillenes A and B were achieved concisely. The key transformation leading to spirobacillene A features a biomimetic intramolecular phenol-enol oxidative coupling reaction, and that leading to spirobacillene B highlights a bio-inspired intramolecular indole-ketone enolate oxidative coupling reaction.