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Several studies are conducted to explain the formation, as well as the characterization of the single self-assembling [alpha],[gamma]-peptide nanotubes. The mechanisms associated with the [alpha],[gamma]-peptide nanotube templating of one-dimensional parallel fullerene arrangements are also discussed.

The design and synthesis of an efficient and selective cyclic A fluorescent sensor is described. The design is refined to increase the affinity constant for cyclin A and also improve the energy transfer efficiency in order to enable the detection of endogenous levels of cyclin in cell lysates.

A ruthenium-catalyzed tandem cyclization-decarbonylation is developed whereby 7-unsubstituted 1,6-diynes have given exo-alkylidenecyclopentanes. The starting point of this process might be the formation of a Ru-vinylidene complex.

The feasibility of a new type of palladium-catalyzed [4 + 3] intramolecular cycloaddition reaction is examined. This new cycloaddition has allowed the synthesis of appealing, stereochemically rich 5,7-fused bicyclic systems from dienylidenecyclopropanes.

The design and characterization of a novel multicomponent network of pyrene and dapoxyl-derivatives [alpha],[gamma]-cyclic peptides that display controlled fluorescent signal output is described. The network system might be particularly relevant for the development of new biosensor systems specifically tailored for studying networks involving homo- and heterodimerization processes.

A new, efficient Ru-catalyzed cyclization of terminal alkynes to cycloalkenes is described. Under appropriate catalytic conditions, cycloisomerization to conjugated aldehydes and new possibilities of C-C formation catalyzed by transition metal vinylidenes might be observed.

A new cascade reaction involving a Ru-catalyzed addition of alkenes to 1,6-[diynes.sup.6] followed by a thermal 6[e.sup.-]pi electrocyclization, is described. The results suggest that Ru-catalyzes addition of cyclic alkenes to 1,6-diynes to give (Z)-hexatrienes followed by thermal 6e(super -)pi electrocyclization to afford bicyclic cyclohexadienes.

The first [3C + 2C] cycloaddition process catalyzed by a ruthenium complex constituting a novel nonmetathetic application of the Grubbs carbene complex is reported. The desired cycloadduct to the reaction was obtained in 11% and 35% yields respectively.

The alk-5-enylidenecyclopropanes of type 1, which can be assembled from allylcyclopropyltosylate, undergoes mild and stereoselective [3+2] intramolecular cycloaddition when it is treated with appropriate palladium catalysts. The results show that the reaction is highly stereoselective and offers a particularly rapid and practical entry to bicyclo[3.3.0]octane systems containing three stereocenters.

The palladium complexes are indicated which are capable of catalyzing the intermolecular cycloaddition of alkynethered methylenecyclopropanes (MCPs). The possibility of undertaking the precursor gathering along with the cycloaddition in a tandem, a single procedure that is extremely easy and realistic towards the bicyclo[3.3.0] octenes is discussed.

Self-assembling peptide nanotubes (SPN) made from cyclic D, L-alpha peptides or from cyclic beta-peptides have structural and functional properties that may be suitable for various applications in biology and materials science. A new member of self-assembling peptides with novel structural and internal cavity, validating the possibility of expanding the SPN class to other hybrid systems is described.

Research has been conducted on the medium-size carbocycles. The method used in cyclization precursor preparation via the ruthenium-catalyzed coupling of 1-trimethylsilyl-1-alkyn-3-ols to allyl ethyl ether is described.

The rearrangement of cyclic allenes via 1,2-dehydrol(10)annulenes is investigated with regard to Diels-Alder reactions.

Inverse electronic effects on the reactivity of CC-1065 (antitumor agent) derivatives, reactivity were studied.

Arynes have been found to undergo palladium-catalyzed cocyclizations with alkynes to produce phenanthrenes. In the case of the reaction with dimethyl acetylenedicarboxylate, naphthalenes were produced. Surprisingly, the reactions with dimethyl acetylenedicarboxylate can be selectively directed toward the formation of phenanthrenes or the formation of naphthalenes by changing the catalyst. This makes it a promising method for the synthesis of polycyclic aromatic compounds.

Cobalt(I)-catalyzed (2+2+2) cycloadditions between 5-hexynenitrile (1) and 1,3-dynes (2) were used for a one-step synthesis of symmetrical, annelated 3,3'substituted 2,2'-bipyridines. The new method requires the regioselective Co(I)-catalyzed cocylization between 5-hexynenitrile with 1,3-diynes, reversing the usual method in bipyridine synthesis.

The article presents information about ruthenium-catalyzed cyclization-decarbonylation of 1,6-terminal diynes mediated by carboxylic acids. A ruthenium-catalyzed tandem cyclization-decarbonylation has been developed whereby 7-unsubstituted 1,6-diynes give exo-alkylidenecyclopentanes. This chemical reaction is predicted to open up opportunities for catalytic alkyne functionalization.

The article describes the [4+3] intramolecular cycloaddition of alkylidenecyclopropanes and dienes using a palladium catalyst. According to the authors, the cycloaddition reaction allows the synthesis of appealing, stereochemically rich 5,7-fused bicyclic systems from readily dienylidenecyclopropanes. They mention that the success of reaction is restricted to dienes blocked in a cisoid conformation and activated by the presence of electron-withdrawing substituents.

The article presents information on a study which is related to palladium-catalyzed intramolecular cycloaddition of Alk-5-enylidenecyclopropanes. A challenging and mechanistically interesting extension of the study concerns the possibility of using alkenes as two-carbon contents in the cycloaddition, a process that could generate bicyclic systems containing up to three stereogenic centers. According to researchers findings, isomeric methylenecyclopropane precursors of type two undergo the cycloaddition, whereas its success is restricted to activated alkenes and is justly dependent on the substrate structure and reaction conditions.