Fingerprints Daylight

Daylight Fingerprints. Daylight Chemical Information Systems, Inc., www.daylight.com, Irvine, CA. 

In addition to molecular weight, percentage saturation of the standard Daylight fingerprint has been used to describe the degree of molecular functionality [78]. Compounds with saturation outside a certain range (e.g., <10% and >60% saturation) can be excluded in order to remove overly simple or complicated molecules that would otherwise pass a simple molecular weight cutoff. 

Fig. 18.8 Similarity profile for filtered set of commercially available compounds. 5000 randomly selected compounds from the Available Chemicals Directory that pass the REOS filter were ranked according to their Tanimoto similarity scores (vertical axis) using Daylight fingerprints. 2886 compounds (58%) had similarity scores below 0.85.

One or more lead molecules may be used as a focusing target. Similarity metrics include Daylight fingerprint Tanimoto similarity. The penalty score for each compound in the library is defined as the distance between it and the most similar lead molecule. The penalty score for the library is the average of the individual compound penalty scores. QSAR predictions and docking scores can also be used in this term. 

The first application using MDS in molecular diversity analysis was introduced by a group at Chiron as a means of reducing the enormous dimensionality of binary chemical descriptors They found that 2048-bit Daylight fingerprints associated with 721 commercially available primary amines could be reduced to only five dimensions that reproduced all 260,000 original dissimilarities with a standard deviation of only 10%. Similarly, only seven dimensions were required to reduce the 642,000 pairwise similarities among a set of 1133 carboxylic acids and acid chlorides to the same standard deviation. 

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