Why has xanthine-based research not progressed rapidly, resulting in a limited number of synthesized xanthine-based molecules, despite its broad pharmaceutical applications and belongingness to the purine family?

Xanthine, with its versatile and structurally rigid scaffold, offers significant potential for molecular diversity in developing derivatives for combinatorial chemistry. However, synthesis methodologies like ring closure and classical condensation routes hinder large-scale diversity in drug development.

Xanthine-based research has not progressed at a full pace, resulting in very few synthesized molecules, primarily due to unfavorable synthesis methodologies such as the ring closure synthetic mechanism and classical condensation routes for generating new derivatives. These methods do not support large-scale diversity in xanthine-based drug development, indicating an urgent need for viable synthesis methods so that new xanthine-based drug candidates can be introduced.