Simplification of the structure

This tactic was used successfully with the alkaloid cocaine (Fig. 7.21). It was well known that cocaine had local anaesthetic properties and it was hoped to develop a local anaesthetic based on a simplified structure of cocaine which could be easily synthesized in the laboratory. Success resulted with the discovery of procaine (or Novocaine) in 1909. 

However, there is a trade-off involved when simplifying molecules. The advantage in obtaining simpler compounds may be outweighed by the disadvantage of increased 

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Still further simplification of the structural requirements for central analgesic activity came from the serendipitous observation that the simple phenyl pi peri dine, meperidine... 

The observation that very significant parts of the cocaine molecule could be deleted from synthetic analogs without loss of biologic activity led to the search for the minimal structural feature consistent with activity. This exercise, sometimes referred to as molecular dissection, not only led to great simplification of the structure of local anesthetics but resulted finally in the preparation of active molecules that bear only the remotest structural relation to the prototype, cocaine. 

Domination of one type of land use, i.e., irrigated farming oriented to monoculture of cotton in the Central Asian republics led to maximum simplification of the structure of the regional socio-economic system, to enhanced dependence on the functioning of one factor - water resources, while almost completely neglecting social dependence on environmental conditions. 

There are usually certain bonds in a molecule whose disconnection in the retrosynthetic direction leads to a significant simplification of the. .. structure. These are termed strategic bonds."... 

In the last century, many plant alkaloids were found to have powerful pharmacological actions. The simplification of the structure of cocaine (7.7) to give the local anaesthetic, procaine ( Novocain ) (7.<9), was the first notable success in modifying the structure of alkaloids to suit the combined needs of manufacturer and clinic (Einhom, 1905). Procaine, unlike cocaine, does not penetrate mucous membranes but is non-addictive and lacks other side effects of cocaine. It at once achieved widespread use as a dental anaesthetic, and is still much used. 

Simplification of the structural system the 3 dimensional structure in practice is simplified to planar multi-linear beam. 

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