Abstract
The natural product combretastatin A-4 (CA4 )
is a potent anti-cancer agent known for its antimitotic and antiangiogenic properties.
The basic structure of CA4 has inspired
the design and synthesis of a variety of medicinally active analogues
that take advantage of the relatively simple stilbenoid architecture
of the molecule. Here, we examine recent advances in the synthesis
of various CA4 -based analogues. A significant
focus is placed on the modifications to the bridging alkene moiety
of the stilbene scaffold for conformationally restricting the structure
in a bioactive form. An effort is also made to discuss promising
ring modifications and replacements, including the incorporation
of indazole and oxindole rings, as well as the design and synthesis
of amino-substituted analogues.
1 Introduction
2 New Approaches for the Synthesis of CA4
3 Synthetic Approaches for the Preparation of CA4 Analogues
3.1 Modification of the Bridging Moiety
3.2 Modification of the Bridging Moiety via Heterocyclic Functionalities
3.3 Macrocyclic Rings Affording Conformational Restriction to
Combretastatin Analogues
4 Amine Substituents on Aryl Rings of Combretastatin Analogues
5 Conclusions
Key words
natural products - drugs - combretastatin - inhibitors - antitumor agents - medicinal
chemistry
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