Synthesis of functionalized azolo(azino)quinazolines by electrophilic cyclization (microreview)

Cyclizations of Alkenyl(Alkynyl)‐Functionalized Quinazolinones and their Heteroanalogues: A Powerful Strategy for the Construction of Polyheterocyclic Structures

“…[56] Quinazolin-4-ones and their heteroanalogues are thus potent pharmacophores, which are extensively harnessed in the design of biologically relevant substances and drugs. It is for biomedically oriented design purposes that synthetic methodologies have been elaborated to construct new pyrimidineheteroannulated, [57][58][59] hetaryl-substituted [10] and hybrid polyheterocyclic nuclei, [10,26,27,60] as an alternative to the initial quinazolinone core. Among annulated polyheterocycles, 2,3fused quinazolinones deserve special attention, as they constitute the framework of natural and synthetic compounds with diverse bioactivity such as the anticancer agent deoxyvasicinone 1, [61] the cholinesterase inhibitor (antidemential) mackinazolinone 2, [62] the broad-spectrum pharmacological agent, in particular, bronchodilator, anti-inflammant and antimicrobial vasicinone 3, [63] and the anti-inflammant isaindi-gotone 4 [64] (Figure 1).…”

“…[57,58] However, it should be noted that summarized evidence on the use of alkenyl(alkynyl)quinazolinones as cyclization substrates is focused mainly on 3-substituted derivatives, whereas their 2-substituted analogues are only briefly addressed in the mini-review. [59] It appears therefore reasonable to systematically…”

“…However, it should be noted that summarized evidence on the use of alkenyl(alkynyl)quinazolinones as cyclization substrates is focused mainly on 3‐substituted derivatives, whereas their 2‐substituted analogues are only briefly addressed in the mini‐review [59] . It appears therefore reasonable to systematically classify and analyze the literature data, as well as the results of our long‐term studies, on the ring‐closure reactions that convert 1‐, 2‐, and 3‐alkenyl(alkynyl) substituted quinazolinones and their heteroanalogues ( 10 – 12 , Figure 2) to polycyclic fused pyrimidine systems.…”