Unique, Unambiguous Representation of Chemical Structures by Computerization of a Simple Notation

New computer representation for chemical structures: Two-level compact connectivity tables

“…Nl, N2, N3, N4, N5, N6 represent the number of single, double, triple, ionic, coordinated, and aromatic bonds, respectively. BCC = 0.1N1 + N2 + 2.5N3 + 3N4 + 5N5 + 8N6 (1) (4) Adjacency Node Code (ANC). This code describes the attribute of adjacent layers of each code; it is defined by eq 2, where NCi is the node code of the i-th adjacency node and NCI > NC2 > NC3 > .... ANC = NCI + NC2/102 + NC3/104 + ... + NCi/102(M) (2) (5) Adjacency Branch Code (ABC).…”

“…Many different methods or systems have been proposed; some of them have been accepted by chemists and widely used in various fields. [1][2][3][4][5][6][7][8][9][10] In the application of computers, to chemistry, however, likely to be in demand is the development of computer representation methods. They are unique and unambiguous, readily understandable, easy to handle, as compact as possible to minimize the computer work space and time consumption, and have good accessibility for handling chemical structure information.…”

The Beilstein Handbook of Organic Chemistry: the first hundred years

“…The organization and methods of using the Beilstein handbook are discussed elsewhere1-6 as are current and possible future trends and developments. 5,7,8 This article is confined to reviewing the historical development of this unique work in the field of organic chemistry.9 First of all, let us review Beilstein's scientific career. At the age of 15 he left Russia to study chemistry.…”