Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Continuous Chirality Measure CCM

One example of a quantitative measure of molecular chirality is the continuous chirality measure (CCM) [39, 40]. It was developed in the broader context of continuous symmetry measures. A chital object can be defined as an object that lacks improper elements of symmetry (mirror plane, center of inversion, or improper rotation axes). The farther it is from a situation in which it would have an improper element of symmetry, the higher its continuous chirality measure. [Pg.418]

Continuous chirality measure is then defined as follows given a configuration of points P = I, its chirality content is determined by finding the nearest configuration of points Pi - 2 which has an improper element of symmetry, and by calculating the distance between the two sets using Eq. (26). [Pg.418]

G is a given symmetry group, Pj are the points of the original configuration, Pi are the corresponding points in the nearest G-symmetric configuration, and n is the total number of the configuration points. For convenience, the expanded scale is S = lOOS . [Pg.418]

In order to calculate S, one has to find the nearest configuration of Pi points that is G-symmetric. In the majority of cases, S is the distance of a chiral object from a reflection mirror. The fblding/unfolding procedure was developed for finding that configuration. [Pg.419]

The S(Gj ) thus obtained is the minimal chirality measure of the given configuration, on a continuous scale of 0 S 100. [Pg.419]


Two general classes of chirality measures have been recognized in the first, the degree of chirality expresses the extent to which a chiral object differs from an achiral reference object, while in the second it expresses the extent to which two enantio-morphs differ from each other [Buda et al., 1992]. The continuous chirality measure (CCM) recently proposed [Zabrodsky and Avnir, 1995] is an example of chirality measure belonging to the first class and is based on the general definition of continuous symmetry measure defined as ... [Pg.64]

Keinan et al. found that the quantitative degree of chirality of substrates correlates with their efficiency of reaction with active sites [7]. The degree of chirality, a global shape descriptor, was determined by the use of the continuous chirality measure (CCM) methodology developed previously, which treats chirahty as a continuous structural property and not as a binary quality (chiral/not chiral) [8]. [Pg.325]

The Measurement of Achirality The Continuous Chirality Measure (CCM) Approach... [Pg.2896]

CCM = continuous chirality measure CSM = continuous symmetry measure. [Pg.2890]


See other pages where Continuous Chirality Measure CCM is mentioned: [Pg.418]    [Pg.493]    [Pg.128]    [Pg.418]    [Pg.493]    [Pg.128]   


SEARCH



Chirality measurement

Continuous Chirality Measure

Continuous measurements

© 2024 chempedia.info