Condensed tetracyclic systems with an isatin fragment in the molecule

Abstract

A new method for the synthesis of the dioxodihydro-1H-benzo [b]furoindole heterocyclic systems from the corresponding isomeric amino acids with the amino groups at positions 2 and 3 is described. By this method it is possible not only to obtain the indicated tetracyclic systems in the form of one isomer but also to interconvert them; from the tetracyclic systems with angular structure it is possible to obtain the corresponding isomers with linear structure and vice versa. The classical Sandmeyer reaction served a model for such transformations.

Recent trends in the chemistry of Sandmeyer reaction: a review

“…Later on, by using same reaction parameters Khoshtariya et al . in 2004 [ 98 ] and 2007 [ 99 ] synthesized 2,3-dioxo-2,3-dihydrobenzo[ b ]furoindoles and dioxodihydro-1 H -benzo[ b ]furoindole, respectively.

Scheme 47 3-Aminodibenzothiophene 198 , a starting precursor for the synthesis of benzo[ b ]thiophenoindoles

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