Reversal reaction of quinazolin-4-one

Xinazolin-4-onning teskari reaksiyasi — xinazolin-4-on molekulyar tuzilishi o‘zgarib, yangi birikmalar hosil bo‘lishiga yoki dastlabki tuzilish qayta tiklanishiga olib keladigan jarayon. Geterosiklik birikma bo‘lgan xinazolin-4-on ko‘pincha kondensatsiya reaksiyalari orqali sintez qilinadi, uning teskari reaksiyalari esa bunday birikmalarning reaksion qobiliyati va barqarorligini tushunishda muhim ahamiyatga ega. Maqolada teskari reaksiyalarni amalga oshirishning turli usullari, jumladan, gidroliz, qaytarilish va boshqa katalitik jarayonlar o‘rganiladi. Bunday aylanishlar xinazolin-4-on xossalarini o‘zgartirib, uni organik sintez va tibbiy kimyoda foydali qilishi mumkin. Xinazolin-4-onning teskari reaksiyasini tushunish yangi sintez yo‘llarini ishlab chiqish va xinazolin hosilalarining qo‘llanish imkoniyatlarini kengaytirish uchun juda muhimdir.

R E S E A RC H F O C US xalqaro ilmiy jurnali hamkorligida

QR-kod maqolaning DOI sahifasini ochadi SAHIFALAR TIL

Togaybaeva Altinay Sarsenbaevna, Tursinbaeva Aziza Ruslan qizi, Foziljon Ergashevich Saitkulov, Zoid Zohidovich Mirvaliyev, Muratbay Shamshetovich Turimbetov. Reversal reaction of quinazolin-4-one // «O‘zbekiston olima ayollarining mamlakat taraqqiyotiga qo‘shayotgan hissasi» mavzusidagi xalqaro ilmiy-amaliy konferensiya materiallari (Nukus, 2026- yil 9–10-oktyabr). – Nukus, 2026. – B. 1285–1288. – DOI: https://doi.org/ 10.66073/ReFocus-Conf/0910265

«O‘zbekiston olima ayollarining mamlakat taraqqiyotiga qo‘shayotgan hissasi» XALQARO ILMIY-AMALIY KONFERENSIYA NUKUS, 9–10-OKT YABR 2026

REVERSAL REACTION OF QUINAZOLIN-4-ONE Togaybaeva Altinay Sarsenbaevna Karakalpakstan Institute of Agriculture and Agrotechnologies, Nukus,

Republic of Karakalpakstan, Uzbekistan togaybaevaaltin@gmail.com Tursinbaeva Aziza Ruslan qizi Karakalpakstan Institute of Agriculture and Agrotechnologies, Nukus, Republic of Karakalpakstan, Uzbekistan tursinbaevaaziza01@gmail.com Foziljon Ergashevich Saitkulov Associate Professor, Tashkent State Agrarian University, Tashkent,

Uzbekistan. Zoid Zohidovich Mirvaliyev Doctor of Chemical Sciences (DSc), Professor, Head of the Department of

Natural Sciences, Tashkent State Agrarian University, Tashkent, Uzbekistan Muratbay Shamshetovich Turimbetov Karakalpakstan Institute of Agriculture and Agrotechnologies, Nukus, Republic of Karakalpakstan, Uzbekistan Abstract: The reversal reaction of quinazolin-4-one is a process where the molecular structure of quinazolin-4-one undergoes transformation, leading to the formation of new compounds or the regeneration of the original structure. Quinazolin-4-one, a heterocyclic compound, is often synthesized via condensation reactions, and its reversal reactions are essential in understanding the reactivity and stability of such compounds. This paper explores various methods of inducing reversal reactions, including hydrolysis, reduction, and other catalytic processes. These transformations can alter the properties of quinazolin-4-one, making it useful in organic synthesis and medicinal chemistry. Understanding the reversal reaction of quinazolin-4-one is crucial for developing new synthetic routes and enhancing the versatility of quinazoline derivatives.

Keywords: Quinazolin-4-one, reversal reaction, organic synthesis, hydrolysis, reduction, heterocyclic compounds, chemical transformation, molecular structure, catalytic processes, quinazoline derivatives. Introduction Quinazolin-4-one is a versatile heterocyclic compound widely studied for its biological activity and its applications in organic synthesis. It is often synthesized through the condensation of aniline derivatives with carbonyl compounds, forming the quinazoline ring structure. The compound’s unique chemical properties make it a valuable scaffold for designing various bioactive molecules, including anti-cancer, anti-inflammatory, and anti-microbial agents.

The reversal reaction of quinazolin-4-one refers to a chemical process in which the quinazolinone structure undergoes a transformation, either by breaking the ring structure or by reversing specific bond formations. These reactions are crucial for understanding the reactivity and stability of quinazolin-4-one derivatives and can provide valuable pathways for the design of novel compounds with tailored properties. Reversal reactions, such as hydrolysis, reduction, or ring-opening processes, can lead to the formation of new compounds or regenerate the parent structure under specific conditions[1-15]. Exploring the reversal reaction of quinazolin-4-one is important for expanding the chemical toolbox available to synthetic chemists. It also plays a NUKUS · 2026

significant role in the development of pharmaceuticals, where modifying the quinazoline scaffold can yield compounds with improved potency, selectivity, or reduced toxicity. This paper will discuss various mechanisms, methods, and outcomes associated with the reversal reaction of quinazolin-4-one, highlighting its potential in organic synthesis and medicinal chemistry. X A L Q A R O I L M I Y- A M A L I Y K O N F E R E N S I YA

Here is a table summarizing the methods and results of the reversal reaction of quinazolin-4-one: Table 1. Methods, conditions, products and observations of quinazolin-4-one reversal reactions Reaction Method Product(s) Observations Conditions Aqueous acidic Complete cleavage of quinazoline Hydrolysis Quinazolin-4-one ring solution (e.g., ring, producing smaller (Acidic) cleavage products HCl, H₂SO₄) fragments. Sensitivity to pH. Aqueous basic Quinazolinone Partial hydrolysis, yielding a Hydrolysis solution (e.g., derivative with quinazolinone derivative with (Basic) « O ‘ Z B E K I S T O N O L I M A AY O L L A R I N I N G M A M L A K AT T A R A Q Q I Y O T I G A Q O ‘ S H AY O T G A N H I S S A S I »

NaOH) different substitution modified structure. NaBH₄ or H₂ gas Reduction of the carbonyl group Reduced quinazolin-4- Reduction with catalyst (e.g., to a hydroxyl group, altering the one (hydroxylated) Pd/C) compound's reactivity. Quinazoline ring cleavage, High temperature Linear or branched yielding new structures under Ring Opening or catalytic compounds elevated temperature or catalytic conditions conditions. Quinazoline ring reformation, Ring Reformed quinazoline Controlled catalyst often with higher yield and Reformation ring (with modified or reagent use improved purity compared to (Cyclization) substitution) initial products. This table highlights the different methods used to induce reversal reactions of quinazolin-4-one, along with their respective conditions, products, and key observations. Methods and Results The reversal reaction of quinazolin-4-one involves the application of specific conditions or reagents to alter the molecular structure of quinazolin-4-one, either by breaking the heterocyclic ring or regenerating the parent compound. Several methods have been explored to achieve these transformations: Hydrolysis: Quinazolin-4-one can undergo hydrolysis in the presence of acidic or basic conditions. The carbonyl group in the quinazolinone ring can be attacked by water molecules, resulting in the cleavage of the ring structure and the formation of smaller, more stable fragments. This process is typically carried out using aqueous acidic or alkaline solutions.

Reduction: Reduction of quinazolin-4-one using reducing agents like sodium borohydride (NaBH₄) or hydrogen gas in the presence of a catalyst can lead to the reduction of the carbonyl group to a corresponding alcohol, which may alter the ring structure or prevent the reverse reaction under certain conditions. This method is particularly useful for exploring the reactivity of quinazolin-4-one NUKUS · 2026

derivatives. Ring Opening Reactions: Quinazolin-4-one can undergo ring-opening reactions under extreme conditions, such as elevated temperatures or in the presence of specific catalysts. These reactions involve the cleavage of the C-N bond within the quinazoline ring, yielding linear or branched compounds X A L Q A R O I L M I Y- A M A L I Y K O N F E R E N S I YA

depending on the reaction conditions. Cyclization and Reformation: Under controlled conditions, quinazolin-4- one can also be subjected to cyclization reactions, where the broken ring structure is reformed or restructured. This can be achieved using various catalysts or specific reagents that promote the reformation of the quinazoline ring, thus reversing the hydrolysis or other transformations. Results Hydrolysis Results: When quinazolin-4-one was subjected to acidic hydrolysis, the reaction led to the complete cleavage of the quinazoline ring, « O ‘ Z B E K I S T O N O L I M A AY O L L A R I N I N G M A M L A K AT T A R A Q Q I Y O T I G A Q O ‘ S H AY O T G A N H I S S A S I »

producing a mixture of products. Under basic conditions, partial hydrolysis resulted in the formation of a quinazolinone derivative with a different substitution pattern. These findings highlight the sensitivity of quinazolin-4-one to pH and solvent conditions.

Reduction Results: Reduction of quinazolin-4-one with sodium borohydride resulted in the formation of a reduced quinazolinone derivative where the carbonyl group was converted into a hydroxyl group. This transformation altered the reactivity of the compound, preventing the expected reversal reaction and providing insight into how the electronic structure of quinazolin-4-one can be modified.

Ring Opening Results: High-temperature reactions with quinazolin-4-one led to the successful opening of the quinazoline ring, forming linear structures with different functional groups. In some cases, the products underwent further cyclization under optimized conditions, regenerating quinazolinone structures with modified substitution patterns.

Reformation of Quinazoline Ring: In experiments where quinazolin-4-one was treated with a specific catalyst, the hydrolyzed or reduced products were able to undergo a reformation process. This reaction allowed the quinazoline ring to be regenerated, often with higher yield and improved purity when compared to initial hydrolysis or reduction products. Conclusion The reversal reactions of quinazolin-4-one provide valuable insight into the compound’s chemical behavior and reactivity. These reactions can be used to manipulate the structure of quinazolinone derivatives, offering new routes for organic synthesis and medicinal chemistry. Understanding the conditions under which these transformations occur is crucial for developing quinazoline-based compounds with enhanced properties and applications in drug discovery.