Ellman's reagent 5,5'-dithio-bis-(2-nitrobenzoic acid), also known as DTNB, was introduced in 1959 as a versatile water-soluble compound for quantitating free sulfhydryl groups in solution. In this procedure, DTNB, a symmetric aryl disulfide, reacts with the free thiol to give a mixed disulfide plus 2-nitro-5-thiobenzoic acid (TNB) which is quantified by its absorbance at 412 nm. Determination of SH groups in proteins by Ellman's reagent after or in the presence of NO treatment is complicated since the reduced form of DTNB, TNB, can be reoxidized by NO back to DTNB, with subsequent loss of absorbance at 412 nm.

Datiscetin is a yellow plant dye from the flavonol group. It exhibited inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA). Datiscetin demonstrated antioxidant activity – it inhibits CCl4-induced microsomal lipid peroxidation and behaved as potent scavenger of the superoxide anion radicals. Datiscetin activated the human constitutive androstane receptor. It inhibited amyloid beta-42 protein aggregation. Datiscetin interacts with amyloid beta-42 protein directly, with monomers and small aggregates.

The mixture of artemotil and alpha-arteether is used in patients with cerebral malaria. Both beta and alpha/beta arteether have comparable activity and are curative at a dose of 5 mg/kg for 3 days against blood-induced Plasmodium cynomolgi B infection in the rhesus monkey; alpha arteether alone is slightly less active, with a 50% cure rate at the above dose. Alpha-arteether is a fourth generation anti-bacterial and anti-fungal drug. Alpha-arteether was found to inhibit the growth of E-coli strains defective in DNA-gyrase enzyme. DNA gyrase mutants were sensitive to α-arteether whereas the wild type of E-coli having intact DNA gyrase genes were not sensitive to α-arteethers. In fact, the isomer of this compound, β-arteether, does not exhibit this activity. The beta-isomer of arteether was characterized by a longer elimination half-life and a relatively larger volume of distribution than the alpha-isomer, suggesting that beta-arteether may be responsible for the prolonged in vivo schizontocidal activity.

Epiquinidine is an alkaloid derived from the bark of the cinchona tree. The most abundant constituents of the Cinchona barks are two pairs of erythro diastereoisomers: quinineand quinidine, which are active antimalarials. Their threo epimers, epiquinine and epiquinidine, are practically inactive. Compared to quinine and quinidine, the 9-epimers had significantly reduced hemozoin inhibition efficiency and did not affect pH-dependent aggregation of ferriprotoporphyrin IX (FPIX) heme. Magnetic susceptibility measurements showed that the 9-epimers perturb FPIX monomer-dimer equilibrium in favor of monomer, and UV-visible (VIS) titrations showed that Epiquinine and Epiquinidine bind monomer with similar affinity relative to quinine and quinidine. However, unique ring proton shifts in the presence of zinc(II) protoporphyrin IX (ZnPIX) indicate that binding of the 9-epimers to monomeric heme is via a distinct geometry.

1β-CALCITRIOL is an Impurity B of Calcitriol. Calcitriol(1,25-Dihydroxyvitamin D3; Rocaltrol ) is the hormonally active form of vitamin D, Calcitriol is the active metabolite of vitamin D3 that activates the vitamin D receptor (VDR). 1-epicalcitriol is a potent antagonist of 1,25(OH)2D3-induced intestinal calcium transport (transcaltachia).

Isobutol (trade name ISOETAM) is a salt of ethambutol and isoniazid methanesulfonate with tuberculostatic and bacteriostatic action. The purpose of this combination is to keep the strong anti-microbic activity of isoniazid in the manner where ethambutol would delay the appearance of resistance.