Organodigermanium Compounds: Structures and Properties

A series of substituted bis(triazole)\nderivatives of organodigermanes\n(<b>1</b>–<b>3</b>) containing reactive phenolic\nand sugar functional groups, [1,4-C<sub>2</sub>HN<sub>3</sub>(<i>R</i>)GePh<sub>2</sub>–]<sub>2</sub> (R = β-(d)-glucopyranoso-C<sub>5</sub>H<sub>5</sub>O(OAc)<sub>3</sub>CH<sub>2</sub>OAc (<b>1</b>); R = CH<sub>2</sub>–1,2,3,5-(HO)C<sub>6</sub>H<sub>2</sub>(<i>t</i>-Bu)<sub>2</sub> (<b>2</b>); and R = CH<sub>2</sub>–1,2,3,5-(HO)C<sub>6</sub>H<sub>2</sub>(CHO)(<i>t</i>-Bu) (<b>3</b>)), was synthesized by\nthe copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction.\nThe structural features (<b>1</b>, XRD analysis) and optical\nproperties (<b>1</b>–<b>3</b>, absorbance, and\nemission) of these digermanium heterocyclic compounds were studied.\nThe antioxidant (DPPH test), lipoxygenase inhibitory (inhibition of\nLOX 1-B), and antiproliferative activities (MTT test; HCT-116, MCF-7,\nA-549 cancer cell lines) of differently substituted <b>1</b>–<b>6</b> (R = <i>p</i>-BrC<sub>6</sub>H<sub>4</sub>CH<sub>2</sub> (<b>4</b>); R = CH<sub>2</sub>COOEt (<b>5</b>); R = CH<sub>2</sub>CH<sub>2</sub>O-<i>p</i>-C<sub>6</sub>H<sub>4</sub>CHO (<b>6</b>)) were investigated, indicating\ntheir promising antioxidant (for <b>2</b> EC<sub>50</sub> 103\n± 4 μM) and lipoxygenase inhibition activity (for <b>4</b> IC<sub>50</sub> 29 ± 2 μM), moderate antiproliferative\nactivities (for <b>5</b> IC<sub>50</sub> 55–71 μM),\nand low toxic properties (WI-38, IC<sub>50</sub> > 36 μM).\nComparison\nof the biological activity of the leader digermanes <b>2</b>, <b>4</b>, and <b>5</b> with related organic triazoles\n1,4-C<sub>2</sub>HN<sub>3</sub>(<i>R</i>) (<b>2a</b>, <b>4a</b>, <b>5a</b>) and monogermanes 1,4-C<sub>2</sub>HN<sub>3</sub>(<i>R</i>)GePh<sub>3</sub> (<b>2b</b>, <b>4b</b>, and <b>5b</b>) indicates the influence of\nthe Ge–Ge fragment.