Synthetic Routes to N-9 Alkylated 8-Oxoguanines; Weak Inhibitors of the Human DNA Glycosylase OGG1

Area of Science:

• Biochemistry
• Molecular Biology
• Medicinal Chemistry

Background:

• 8-oxoguanine DNA glycosylase (OGG1) plays a crucial role in base excision repair (BER).
• DNA repair mechanisms like BER are vital for counteracting DNA damage from cancer therapies.
• Targeting DNA repair enzymes offers a strategy for enhancing chemo- and radiation therapy efficacy.

Purpose of the Study:

• To synthesize and evaluate 9-alkyl-8-oxoguanines as potential inhibitors of OGG1.
• To investigate synthetic routes for generating 8-oxoguanine derivatives.
• To identify novel compounds that could modulate OGG1 activity in cancer treatment.

Main Methods:

• Exploration of synthetic pathways for 8-oxoguanines, starting from 6-chloroguanine.
• Key synthetic steps included N-9 alkylation, C-8 bromination, and simultaneous hydrolysis of halides.
• Evaluation of synthesized 8-oxoguanines and related 6-chloro-8-oxopurines for OGG1 inhibitory activity.

Main Results:

• The synthesized 9-alkyl-8-oxoguanines demonstrated weak inhibitory effects against OGG1.
• A specific synthetic route involving N-9 alkylation followed by C-8 bromination and hydrolysis was identified as optimal.
• Byproducts, 6-chloro-8-oxopurines, exhibited slightly enhanced OGG1 inhibition compared to the target 8-oxoguanines.

Conclusions:

• While 9-alkyl-8-oxoguanines are not potent OGG1 inhibitors, their synthesis provides valuable chemical entities.
• The study highlights 6-chloro-8-oxopurines as potentially more promising scaffolds for OGG1 inhibition.
• Further research into related purine analogs may yield effective OGG1 modulators for cancer therapy.