topological indices are the numerical value associated with chemical constitution purporting for correlation ofchemical structure with various physical properties, chemical reactivity or biological activity. graph theory is adelightful playground for the exploration of proof techniques in discrete mathematics and its results haveapplications in many areas of sciences. one of the useful indices ...

Topological indices are the numerical value associated with chemical constitution purporting for correlation ofchemical structure with various physical properties, chemical reactivity or biological activity. Graph theory is adelightful playground for the exploration of proof techniques in Discrete Mathematics and its results haveapplications in many areas of sciences. One of the useful indices ...

The synthesis and crystal structural characterization of new compounds 2-6 were accomplished. As a common synthetic methodology, the Diels-Alder reaction was applied to 9,9',10,10'-tetradehydrodianthracene (TDDA) (7) to furnish the [12]annulenes 2 and 3 [16]annulene 6 and adduct 5.

The purpose of this study was to understand the relationship between the vibrational structure and geometry of selected porphyrin-like macrocyclic compounds with double intramolecular hydrogen bonds, in the ground electronic state, by vibrational spectroscopy and computational quantum chemistry methods. The porphyrin, porphycene (constitutional isomer of porphyrin), and dibenzo[b,i][1,4,8,11]te...

This report describes the synthetic strategies toward and optoelectronic properties of substructures of the non-natural, planar carbon networks graphyne and graphdiyne, which are based on the dehydrobenzo[12]annulene and dehydrobenzo[18]annulene framework, respectively.

microorganisms are important components of soil. some soil filamentous fungi such aspenicilium produce many bioactive small molecules, or secondary metabolites, that range frombeneficial bioactive compounds to harmful toxins. in this study, the metabolites of threepenicillium species (p. goditanum, p. moldavicum and p. corylophilum) were extracted byadding ethyl acetate to liquid cultures. the ...

Ten new cembrane-based diterpenes, locrassumins A-G (1-7), (-)-laevigatol B (8), (-)-isosarcophine (9), and (-)-7R,8S-dihydroxydeepoxysarcophytoxide (10), were isolated from a South China Sea collection of the soft coral Lobophytum crassum, together with eight known analogues (11-18). The structures of the new compounds were determined by extensive spectroscopic analysis and by comparison with ...

Microorganisms are important components of soil. Some soil filamentous fungi such asPenicilium produce many bioactive small molecules, or secondary metabolites, that range frombeneficial bioactive compounds to harmful toxins. In this study, the metabolites of threepenicillium species (P. goditanum, P. moldavicum and P. corylophilum) were extracted byadding ethyl acetate to liquid cultures. The ...

A new family of belt-shaped carbon structures, called Escherynes, is theoretically proposed using the octadehydro annulene (ODA) skeleton as a building block. Several ODA rings are fused together and cyclized to form belt-structures. Two isomeric forms of the Escherynes are considered, Hückel and Möbius. We demonstrate that these compounds have thermodynamical and kinetic stabilities comparable...

Sesqui- and sesterterpenes of ophiobolin and fusicoccin families are important synthetic targets because of complexity of structure and potentially useful physiological activities, including anti-tumor activity. A synthesis of versatile building blocks for these terpenoids is described. Cyclopenta[8]annulene rings system with properly dislocated substituents was constructed using as key steps r...