4-Chloromercuribenzoic acid

Chemical Properties

4-CHLOROMERCURIBENZOIC ACID is White Solid

Uses

4-CHLOROMERCURIBENZOIC ACID can be used to inhibit some enzymes that require unmodified cysteine residues (e.g., adenylyl cyclase).

Uses

A useful sulfhydryl reagent that reacts with Histidine 225C, a residue of the NhaA-Na/H Antiporter of Escherichia Coli

Definition

ChEBI: P-chloromercuribenzoic acid is a mercuribenzoic acid and a chlorine molecular entity. It is functionally related to a benzoic acid.

Biological Activity

DHFR catalyzes the nicotinamide adenine dinucleotide phosphate (NADPH)-dependent reduction of dihydrofolate to tetrahydrofolate, and it is essential for the synthesis of thymidylate, purines and several amino acids. Expression of methotrexate (MTX)-resistant variants of DHFR in normal hematopoietic cells is a potential strategy to permit administration of larger doses of MTX by alleviating drug toxicity in normal cells and tissues th at are drug sensitive.

Safety Profile

Poison by intraperitoneal route. See also MERCURY COMPOUNDS. When heated to decomposition it emits very toxic fumes of Cland Hg.

Purification Methods

Its suspension in water is stirred with enough 1M NaOH to dissolve most of it: a small amount of insoluble matter is removed by centrifugation. The chloromercuribenzoic acid is then precipitated by adding 1M HCl and centrifuged off. The precipitation is repeated twice. Finally, the precipitate is washed three times with distilled water (by centrifugation), then dried in a thin layer under vacuum over P2O5 [Boyer J Am Chem Soc 76 4331 1954]. Chloromethylphosphonic acid dichloride [1983 -26 -2] M 167.4, b 50o/0.5mm, 52 -53(59)o/2mm, 63-65o/3mm, 78 -79o/10mm, 87 -88o/15mm, 102-103o/30mm, d 4 1.638, n D 1.4971. It is fractionally distilled using a short Claisen column and redistilled. The aniline salt has m 199-201o. The 3 1P NMR has a single peak at -38±2 ppm from 85% H3PO4. [Kinnear & Perren J Chem Soc 3437 1952, NMR: van Wazer et al. J Am Chem Soc 78 5715 1956, McConnell et al. J Org Chem 22 462 1957, Beilstein 1 III 2593, 1 IV 3068.]