Organodigermanium Compounds: Structures and Properties

Abstract

A series of substituted bis(triazole) derivatives of organodigermanes (1–3) containing reactive phenolic and sugar functional groups, [1,4-C₂HN₃(R)GePh₂–]₂ (R = β-(d)-glucopyranoso-C₅H₅O(OAc)₃CH₂OAc (1); R = CH₂–1,2,3,5-(HO)C₆H₂(t-Bu)₂ (2); and R = CH₂–1,2,3,5-(HO)C₆H₂(CHO)(t-Bu) (3)), was synthesized by the copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction. The structural features (1, XRD analysis) and optical properties (1–3, absorbance, and emission) of these digermanium heterocyclic compounds were studied. The antioxidant (DPPH test), lipoxygenase inhibitory (inhibition of LOX 1-B), and antiproliferative activities (MTT test; HCT-116, MCF-7, A-549 cancer cell lines) of differently substituted 1–6 (R = p-BrC₆H₄CH₂ (4); R = CH₂COOEt (5); R = CH₂CH₂O-p-C₆H₄CHO (6)) were investigated, indicating their promising antioxidant (for 2 EC₅₀ 103 ± 4 μM) and lipoxygenase inhibition activity (for 4 IC₅₀ 29 ± 2 μM), moderate antiproliferative activities (for 5 IC₅₀ 55–71 μM), and low toxic properties (WI-38, IC₅₀ > 36 μM). Comparison of the biological activity of the leader digermanes 2, 4, and 5 with related organic triazoles 1,4-C₂HN₃(R) (2a, 4a, 5a) and monogermanes 1,4-C₂HN₃(R)GePh₃ (2b, 4b, and 5b) indicates the influence of the Ge–Ge fragment.