5-Formylcytosine mediated DNA-peptide cross-link induces predominantly semi-targeted mutations in both Escherichia coli and human cells.

Histone proteins can become trapped on DNA in the presence of 5-formylcytosine (5fC) to form toxic DNA-protein conjugates. Their repair may involve proteolytic digestion resulting in DNA-peptide cross-links (DpCs). Here, we have investigated replication of a model DpC comprised of an 11-mer peptide (NH-GGGKGLGK∗GGA) containing an oxy-lysine residue (K∗) conjugated to 5fC in DNA.

Diels-Alder/Ene Reactivities of 2-(1'-Cycloalkenyl)thiophenes and 2-(1'-Cycloalkenyl)benzo[]thiophenes with -Phenylmaleimides: Role of Cycloalkene Ring Size on Benzothiophene and Dibenzothiophene Product Distributions.

Scaffolds of thiophene and benzothiophene are the important class of bioactive compounds found abundant in nature. The Diels-Alder reactions of 2-(1'-cycloalkenyl)thiophenes and 2-(1'-cycloalkenyl)benzo[]thiophenes having the alkene groups present in five-, six-, seven-, eight-, and twelve-membered rings with substituted -phenylmaleimides are characterized. The size of the cycloalkene rings plays a critical role in dictating the product distributions of expected and isomerized Diels-Alder adducts.

Fe-Catalyzed Domino Intramolecular Nucleophilic Substitution of 4-Hydroxychromen-2-one and Pyran-2-one/Ring Opening of Activated Arene: An Easy Access to 2,3-Disubstituted Furo[3,2,-]coumarins and Furo[3,2,-]pyran-4-ones via Nonsymmetric Triarylmethanes.

A one-pot synthesis of functionalized 2,3-disubstituted furo[3,2,-]coumarins and furo[3,2,-]pyran-4-ones under hydrated ferric sulfate catalysis was performed. It was revealed that the reaction proceeds with intramolecular cyclofunctionalization of nonsymmetric triarylmethanes via ring opening of 2-methylfuran followed by recyclization, resulting in the selective formation of desired products. The versatility of this method was demonstrated via the succinct synthesis of an anticoagulant agent analogue and 2,3-disubstituted benzofurans.

Synthesis, antioxidant and antimicrobial activity of novel vanillin derived piperidin-4-one oxime esters: preponderant role of the phenyl ester substituents on the piperidin-4-one oxime core.

The study has been achieved the efficient synthesis of vanillin derived piperidin-4-one oxime esters (5a-m) via four step reaction involved Mannich reaction of vanillin, acetone and ammonium acetate to obtain 2,6-bis(4-hydroxy-3-methoxyphenyl)-piperidin-4-one 2 followed by N-methylation and oximation. Further, to enhance the biological activity of vanillin derived piperidin-4-one oxime core, esterification of 4 with substituted benzoyl chlorides in the presence of strong organic base t-BuOK accomplished a series of vanillin derived piperidin-4-one oxime esters (5a-m). The synthesized analogues are screened for their antioxidant and antimicrobial studies and the preponderant effect of the phenyl ester substituents on the biological activity of piperidin-4-one oxime core was demonstrated.

Synthesis of benzofuran based 1,3,5-substituted pyrazole derivatives: as a new class of potent antioxidants and antimicrobials--a novel accost to amend biocompatibility.

In search for a new antioxidant and antimicrobial agent with improved potency, we synthesized a series of benzofuran based 1,3,5-substituted pyrazole analogues (5a-l) in five step reaction. Initially, o-alkyl derivative of salicyaldehyde readily furnish corresponding 2-acetyl benzofuran 2 in good yield, on treatment with 1,8-diaza bicyclo[5.4.