O-VANİLİN TEMELLİ SCHIFF BAZI LİGANDI İLE YENİ BİR Co(II) KOMPLEKSİNİN SENTEZİ, KARAKTERİZASYONU, BSA BAĞLANMA AKTİVİTESİ VE ADME TAHMİNLERİ

Abstract

Bu çalışma, o-vanillin bazlı bir Schiff bazı ligandının ve Co(II) kompleksinin sentezi, karakterizasyonu, bovin serum albümini (BSA) ile etkileşimi ve farmakokinetik özelliklerini raporlamaktadır. Ligand (H₂L), izonitrozofenil hidrazin ile o-vanillin arasındaki kondenzasyon reaksiyonu ile sentezlenmiş; Co(II) kompleksi [Co(HL)₂] ise sentezlenen ligandın kobalt(II) asetat monohidrat ile tepkimesiyle hazırlanmıştır. Ligand; elementel analiz, UV-Vis, FTIR, NMR spektroskopisi ile, Co(II) kompleksi ise elementel analiz, UV-Vis, FTIR spektroskopisi, manyetik duyarlılık ölçümü ve kütle spektrometrisi ile karakterize edilmiş ve bu sayede kompleksin oktahedral geometriye sahip olduğu doğrulanmıştır. Co(II) kompleksinin BSA ile bağlanma çalışmaları, statik söndürme mekanizması aracılığıyla orta düzeyde bir bağlanmayı (Kbin= 8.74x10³ M⁻¹) ortaya koymuş; bu durum termodinamik hesaplamalarla (ΔG=–22.49 kJ.mol⁻¹) desteklenmiştir. Ayrıca, ligand da daha düşük bir bağlanma afinitesiyle (Kbin=1.36x10³ M⁻¹) BSA ile etkileşim göstermiştir; bu da metal koordinasyonunun protein etkileşimini önemli ölçüde artırdığını göstermektedir. Co(II) kompleksine ait ADME tahminleri, 651.53 g/mol moleküler ağırlık, 151.54 Ų polar yüzey alanı (TPSA), orta düzeyde esneklik ve iyi düzeyde fizikokimyasal kararlılık gibi umut verici farmakokinetik özellikleri göstermiştir. Bununla birlikte, sınırlı gastrointestinal emilim ve kan-beyin bariyeri geçirgenliğinin olmaması, bu kompleksin periferik tedavi uygulamaları için uygun olabileceğini düşündürmektedir. Gelecek çalışmalarda, bu umut verici Co(II) kompleksi ve Schiff bazı ligandının terapötik etkinliğini ve güvenlik profilini doğrulamak amacıyla ayrıntılı sitotoksisite testleri ve farmakokinetik değerlendirmeler yapılacaktır.

Keywords

• Co(II) Kompleksi
• O-Vanilin
• Schiff Bazı
• BSA Bağlanma
• ADME

SYNTHESIS, CHARACTERIZATION, BSA BINDING ACTIVITY AND ADME PREDICTIONS OF A NEW Co(II) COMPLEX WITH O-VANILLIN-BASED SCHIFF BASE LIGAND

Abstract

This study reports the synthesis, structural characterization, bovine serum albumin (BSA) binding activity, and pharmacokinetic properties of an o-vanillin-based Schiff base ligand and its Co(II) complex. The ligand (H2L) was synthesized via condensation reaction between isonitrosophenyl hydrazine and o-vanillin, and the Co(II) complex [Co(HL)2] was prepared by reacting the ligand with cobalt(II) acetate monohydrate. The ligand was characterized by elemental analysis, UV-Vis, FTIR, NMR spectroscopy, while Co(II) complex was characterized by elemental analysis, UV-Vis, magnetic susceptibility, FTIR and mass spectrometry, confirming successful complex formation with octahedral geometry. BSA binding studies of Co(II) complex demonstrated moderate binding (Kbin=8.74x103 M-1) via static quenching mechanism, supported by thermodynamic calculations (ΔG=-22.49 kJ.mol-1). The ligand also exhibited BSA binding with a lower affinity (Kbin=1.36x103 M-1), indicating that metal coordination significantly enhances protein interaction. In silico ADME predictions of Co(II) complex indicated promising pharmacokinetics characterized by a molecular weight of 651.53 g/mol, polar surface area (TPSA = 151.54 Ų), moderate flexibility, and reasonable physicochemical stability. However, limited gastrointestinal absorption and lack of blood-brain barrier permeability, suggest potential suitability for peripheral therapeutic applications. Future studies will involve detailed cytotoxicity assays and pharmacokinetic evaluations to validate the therapeutic efficacy and safety profile of this promising Co(II) complex and Schiff base ligand.

Keywords

• Co(II) Complex
• o-Vanillin
• Schiff Base
• BSA Binding
• ADME

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