Toxophilic groups

When Ehrlich had transferred his interests from large molecules to small ones, he drew on part of his side-chain (immunological) hypothesis to explain the mode of action of chemotherapeutic agents. They too, he supposed, had distinct haptophoric and toxophilic groups (he demonstrated this for arsenicals see the end of this section), and they combined with cellular receptors whose normal function was to take part in cellular nutrition or respiration (Ehrlich, 1908). 

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