Trimethylolethane or trimethylolpropane mono or di[hydroxycarboxylic acid(C=523) ester] C??? ??, ??, ??

Trimethylolethane or trimethylolpropane mono or di[hydroxycarboxylic acid(C=523) ester] ?? ?? ? ???

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Trimethylolethane or trimethylolpropane mono or di[hydroxycarboxylic acid(C=523) ester] ?? ??