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Which number replaces the qu...

Which number replaces the question mark?

Correct answers: 122

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Synthetic quinine

In 1944, the first synthetic quinine was produced by Dr. Robert Burns Woodward (on his birthday) and Dr. William von Eggers Doering at the Converse Memorial Laboratory, Harvard University, Cambridge, Mass. Quinine, an anti-malarial drug, is an organic chemical with the formula C20H24N2O2.

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