Wiswesser line notation (WLN), invented by William J. Wiswesser in 1949, was the first line notation capable of precisely describing complex molecules. It was the basis of ICI Ltd's CROSSBOW database system developed in the late 1960s. WLN allowed for indexing the Chemical Structure Index (CSI) at the Institute for Scientific Information (ISI). It was also the tool used to develop the CAOCI (Commercially Available Organic Chemical Intermediates) database, the datafile from which Accelrys' (successor to MDL) ACD file was developed. WLN is still being extensively used by BARK Information Services. Descriptions of how to encode molecules as WLN have been published in several books.
Examples 1H : methane 2H : ethane 3H : propane 1Y : isobutane 1X : neopentane Q1 : methanol 1R : toluene 1V1 : acetone 2O2 : diethyl ether 1VR : acetophenone ZR CVQ : 3-aminobenzoic acid QVYZ1R : phenylalanine QX2&2&2 : 3-ethylpentan-3-ol QVY3&1VQ : 2-propylbutanedioic acid L66J BMR& DSWQ IN1&1 : 6-dimethylamino-4-phenylamino-naphthalene-2-sulfonic acid QVR-/G 5 : pentachlorobenzoic acid T5NN DNJ AVN3&2 CSW3 : Epronaz
References
External links Everything Old is New Again: Wiswesser Line Notation (WLN)