Harnessing coumarin-thio(seleno)cyanate conjugates: potent <i>In vivo</i> antiproliferative agents targeting carbonic anhydrases

We synthesised coumarin-based derivatives bearing thio- and selenocyanates to selectively inhibit tumour-associated carbonic anhydrases (CAs) IX and XII and to exert antiproliferative effects on tumour cells. Structural variations included chalcogen atom type (S, Se), substitutions at C-3/C-4, and tether length at C-7 of the coumarin core. Thiocyanates <b>4</b> and <b>7b</b> showed potent CA IX/XII inhibition (<i>K</i>_i = 17.9–27.4 nM) with &gt;5000-fold selectivity over off-target isoforms (CAs I and II). Selenocyanate <b>8a</b> exhibited strong antiproliferative activity (GI₅₀ = 0.78–2.6 µM) across six human solid tumour cell lines. Mechanistic studies revealed a cytostatic effect <i>via</i> cell cycle arrest and reduced mitotic progression. <i>In vivo</i> assays in <i>Caenorhabditis elegans</i> confirmed selective cytostatic action of selenocyanate <b>8c</b>, reducing tumorous germline size without affecting healthy tissues at therapeutic doses.本研究合成了带有硫氰基与硒氰基的香豆素类衍生物，用于选择性抑制肿瘤相关碳酸酐酶（carbonic anhydrases, CAs）IX与XII亚型，并对肿瘤细胞发挥抗增殖活性。该类衍生物的结构修饰维度包括：硫族原子（chalcogen atom）类型（硫S、硒Se）、香豆素母核（coumarin core）C-3/C-4位的取代基团，以及C-7位的连接臂长度。其中硫氰基衍生物<b>4</b>与<b>7b</b>展现出强效的CA IX/XII抑制活性，抑制常数<i>K</i>_i = 17.9–27.4 nM，相较于脱靶同工型CA I与II，其选择性超过5000倍。硒氰基衍生物<b>8a</b>则在六种人体实体瘤细胞系中表现出显著的抗增殖活性，半数生长抑制浓度<i>GI</i>₅₀ = 0.78–2.6 µM。机制研究表明，该类衍生物通过<i>via</i>细胞周期阻滞与有丝分裂进程减缓，发挥细胞生长抑制作用。以秀丽隐杆线虫（Caenorhabditis elegans）为受试对象的<i>in vivo</i>实验证实，硒氰基衍生物<b>8c</b>具有选择性细胞生长抑制活性：在治疗剂量下，其可缩小肿瘤性生殖系体积，且不会对健康组织造成不良影响。