A Multitarget Approach toward the Development of 8-Substituted Purines for Photoprotection and Prevention of UV-Related Damage

In environmental abundance, UV is the most important modifiable risk factor for skin cancer and many other skin diseases such as early photo-aging. Among solar radiation, ultraviolet (UV) is mainly responsible for inducing skin problems. In search of novel photoprotective purines, a new series of 8-substituted purines were synthesized from commercially available 6-hydroxy-4,5-diaminopyrimidine hemisulfate or 4,5-diaminopyrimidine. All the title compounds were investigated for their UV-filter, antioxidant, antifugal and antiproliferative activities. For the photoprotective assays we used a diffuse transmittance technique to determine the SPF in vitro, and DPPH and FRAP tests for antioxidant activity evaluation of the more potent compounds. Compound 26 proved, among the others, to be a good radical-scavenger and was also endowed with broad-spectrum UVA filtering capabilities, suitable to be developed as a protective molecule