Benzene Derivatives with Achiral and Chiral Substituents and Relevant Derivatives Derived fromD6hSkeletons. Symmetry-Itemized Enumeration and Symmetry Characterization by the Unit-Subduced Cycle Index Approach

1999 ◽  
Vol 39 (1) ◽  
pp. 151-163 ◽  
Author(s):  
Shinsaku Fujita
2021 ◽  
Vol 87 (3) ◽  
pp. 481-525
Author(s):  
Shinsaku Fujita ◽  

Combined-permutation representations (CPRs) for characterizing -skeletons (a benzene skeleton, a Haworth-projected skeleton, a superphane skeleton, and a coronene skeleton) are constructed by starting from respective sets of generators, where the permutation of each generator is combined with a mirror-permutation of 2-cycle to treat both achiral and chiral substituents under the GAP system. Thereby, the CPR of degree 8 (= 6 + 2) for the benzene skeleton, the CPR of degree 14 (= 12 + 2) for the Haworth-projected skeleton, the CPR of degree 14 (= 12 + 2) for the superphane skeleton, the CPR of degree 14 (= 12 + 2) for the coronene skeleton are generated to give primary mark tables (tables of marks) based on these CPRs. These primary mark tables generated by the GAP system are different in the sequence of subgroups from each other, although they stem from the same point group . They are unified into a single standard mark table by means of a newly-devised GAP function MarkTableforUSCI. Moreover, another newly-devised GAP function constructUSCITable is employed to construct a standard USCI-CF (unit-subduced-cycle-index-with-chirality-fittingness) table concordantly. After a set of PCI-CFs (partial cycle indices with chirality fittingness) is calculated for each skeleton, symmetry-itemized combinatorial enumeration is conducted by means of the PCI method of Fujita’s USCI approach (S. Fujita, Symmetry and Combinatorial Enumeration in Chemistry, Springer-Verlag, Berlin-Heidelberg, 1991).


2010 ◽  
Vol 75 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Ali Moghani ◽  
Naghdi Sedeh ◽  
Reza Sorouhesh

Using non-rigid group theory, it was previously shown that the full non-rigid group of 2,4-dimethylbenzene is an ummatured and isomorphic to the group C2?(C3wrC2) of order 36, where Cn is the cyclic group of order n, the symbols ? and wr stand for the direct and wreath products, respectively. Herein, it is first shown that this group has 12 dominant classes. Then, the Markaracter Table, the Table of all integer-valued characters and the unit subduced cycle index (USCI) Table of the full non-rigid group of 2,4-dimethylbenzene are successfully derived for the first time.


1991 ◽  
Vol 88 ◽  
pp. 509-514 ◽  
Author(s):  
MA Cuevas Diarte ◽  
T Calvet ◽  
M Labrador ◽  
E Estop ◽  
HAJ Oonk ◽  
...  

Author(s):  
Autumn Flynn ◽  
Kelly McDaniel ◽  
Meredith Hughes ◽  
David Vogt ◽  
Nathan Jui

A photocatalytic system for the dearomative hydroarylation of benzene derivatives has been developed. Using a combination of an organic photoredox catalyst and an amine reductant, this process operates through a reductive radical-polar crossover mechanism where aryl halide reduction triggers a regioselective cyclization event, giving rise to a range of complex spirocyclic cyclohexadienes. This light-driven protocol functions at room temperature in a green solvent system (aq. MeCN), without the need for precious metal-based catalysts or reagents, or the generation of stoichiometric metal byproducts.


Think India ◽  
2019 ◽  
Vol 22 (2) ◽  
pp. 174-187
Author(s):  
Harmandeep Singh ◽  
Arwinder Singh

Nowadays, internet satisfying people with different services related to different fields. The profit, as well as non-profit organization, uses the internet for various business purposes. One of the major is communicated various financial as well as non-financial information on their respective websites. This study is conducted on the top 30 BSE listed public sector companies, to measure the extent of governance disclosure (non-financial information) on their web pages. The disclosure index approach to examine the extent of governance disclosure on the internet was used. The governance index was constructed and broadly categorized into three dimensions, i.e., organization and structure, strategy & Planning and accountability, compliance, philosophy & risk management. The empirical evidence of the study reveals that all the Indian public sector companies have a website, and on average, 67% of companies disclosed some kind of governance information directly on their websites. Further, we found extreme variations in the web disclosure between the three categories, i.e., The Maharatans, The Navratans, and Miniratans. However, the result of Kruskal-Wallis indicates that there is no such significant difference between the three categories. The study provides valuable insights into the Indian economy. It explored that Indian public sector companies use the internet for governance disclosure to some extent, but lacks symmetry in the disclosure. It is because there is no such regulation for web disclosure. Thus, the recommendation of the study highlighted that there must be such a regulated framework for the web disclosure so that stakeholders ensure the transparency and reliability of the information.


1985 ◽  
Vol 20 (2) ◽  
pp. 36-43 ◽  
Author(s):  
Klaus L.E. Kaiser ◽  
Juan M. Ribo ◽  
Brian M. Zaruk

Abstract This paper gives the results of part of a systematic investigation into contaminant toxicity to Photobacterium phosphoreum in the Microtox™ test. Reported are the toxicity values for 39 para-chloro substituted benzene derivatives of the general formula l-Cl-C6h4-4-X=CH2CH(NH2)COOH, F, SO2NH2, OCH2COOH, CH2COOH, CONHNH2, NHCOCH3, CONH2, CH=CHCOOH, SeOOH, CH2NH2, CH2CH2NH2, NO2, H, CF3, CHO, CH2OH, OH, CH3, CCl3, COCH3, COOH, NH2, SO2C6H5, Cl, CH2COCH3, COCl, CN, OCH3, NCO, NHCH3, I, COC6H5, CH2Cl, SH, CH2SH, NCS, CH2CN and SO2C6H4Cl. Except for the last compound, whose solubility is below the required concentration, the toxicities increase in the presented order with a total range of more than three orders of magnitude. The data are discussed in terms of quantitative structure-toxicity correlations with compound-specific structural parameters. In combination with a previously developed submodel on chlorinated benzenes, phenols, nitrobenzenes and anilines, the observed relationships allow the prediction of the toxicity of some 780 possible chloro derivatives of the general formula C6H5-nClnX, where n=<5 and X is a functional group as listed above.


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