Reference

Studies on the reduction of 2,6-dichlorophenolindophenol by 6-substituted 3-hydroxy-4-pyrones, using a stopped-flow method

Studies on the reduction of 2,6-dichlorophenolindophenol by 6-substituted 3-hydroxy-4-pyrones, using a stopped-flow method. Obata, Hitoshi; Fujiwara, Nobuki; Tanishita, Junichi; Tokuyama, Tai (Fac. Eng., Kansai Univ., Suita 564, Japan). Agric. Biol. Chem., 48(11), 2615-19 (English) 1984. CODEN: ABCHA6. ISSN: 0002-1369. DOCUMENT TYPE: Journal CA Section: 17 (Food and Feed Chemistry) The redn. of 2,6-dichlorophenolindophenol (DCIP) [956-48-9] by 6-substituted-3-hydroxy-4-pyrones was studied in the pH range of 3.0 to 7.8, using a stopped-flow app. Kinetic characteristics of 6-substituted 3-hydroxy-4-pyrones are shown as the apparent 1st-order rate const., kapp, or the 2nd-order rate const., k. The plot of log k against pH was different from those obtained for the reactions of L-ascorbic acid and triose reductone with DCIP. The log (k/kH) of 6-substituted 3-hydroxy-4-pyrone solns. at acidic pH values have been correlated with the difference in C-3 chem. shift vs. a std. compd. (Ddc-3) values for 3-hydroxy-4-pyrone [496-63-9].

Utility of 2,6-dichlorophenolindophenol for the spectrophotometric determination of certain alkaloids

Utility of 2,6-dichlorophenolindophenol for the spectrophotometric determination of certain alkaloids. Abdel-Salam, M.; Mahrous, M. S.; Issa, A. S. (Fac. Pharm., Univ. Alexandria, Alexandria, Egypt). J. Pharm. Belg., 41(4), 226-30 (English) 1986. CODEN: JPBEAJ. ISSN: 0047-2166. DOCUMENT TYPE: Journal CA Section: 64 (Pharmaceutical Analysis) Strychnine [57-24-9], brucine [357-57-3], atropine [51-55-8], and quinine [130-95-0] were detd. by spectrophotometry based on formation of blue chromogen with 2,6-dichlorophenolindophenol (I) [956-48-9] (0.1% wt./vol.) in CHCl3 medium. The color was stable for 1 h and the absorbance was measured at 580-603 nm. Beer's law was valid within the concn. range of 0.4-2 mg% for atropine and quinine and 4.0-20 mg% for strychnine and brucine. Recoveries were 99.68-102.055% and relative std. deviations 0.53-0.74%. Some alkaloids produced no color with I probably due to their weak basicity.