Soviet chemist Nikolai Semenovich Kurnakov

Nikolai Semenovich Kurnakov

-Biography:Kurnakov was born in Nolinsk, Kirov Oblast. He attended a high school at Nizhny Novgorod and later studied at the mining institute in St. Petersburg. He published his first paper on alum crystallization and sodium thioantimoniate in 1882. In the same year he graduated as a mining engineer...

 utilised the phenomonon of trans-effect in distinguishing the pairs of cis- and trans-isomers of square complexes of [PtA2X2] (A=NH3, X=halogen or acid radical) type by treating them with thiourea

Thiourea

Thiourea is an organosulfur compound of with the formula SC2 . It is structurally similar to urea, except that the oxygen atom is replaced by a sulfur atom, but the properties of urea and thiourea differ significantly. Thiourea is a reagent in organic synthesis. "Thioureas" refers to a broad...

. This is as know the famous kurnakov reaction.

Uses

Kurnakov test is used to distinguish between cisplatin

Cisplatin

Cisplatin, cisplatinum, or cis-diamminedichloroplatinum is a chemotherapy drug. It is used to treat various types of cancers, including sarcomas, some carcinomas , lymphomas, and germ cell tumors...

 and transplatin. In hot aqueous solution, the cis compound reacts with aqueous thiourea to give a deeper yellow solution from which yellow needles of tetrakis (thiourea) platinum(II)chloride deposit on cooling, while the trans compound gives a colourless solution from which snow white needles of trans-bis(thiourea)diaammineplatinum(II) deposit on cooling.