Ot Nitrophenol

NlTRO-2-NAPHTHOL, 13, 78 ot-Nitrophenol, IS, 88 -Nitrophenol, 15, 6 i>-NlTROPHENYL ISOCYANATE, 14, 72 o-Nitrophenylsulfur CHLORIDE, 16, 45 4-Nitrophthauc acid, 16, 56... 

One purpose of metabolic transformations has been assumed to be conversion of a xenobiotic into more water-soluble form (18) as shown by partition coefficients (19 ), the hydrophil icity oT p-nitrophenol (Kp 81) is much greater than that of PNA (Kp 107), and that of the corresponding nitrophenyl sulfate and glycosides must be greater still. On the other hand, while p-anisidine (Kp 9) is relatively soluble compared to PNA, the advantage would seem to be lost in conversion to "insoluble" p-methoxyacetanilide (Kp 14). 

Holmes et al. (1998) performed two enzymatic reactions, the lipase-catalyzed hydrolysis of y>-nitrophenol butyrate and lipoxygenase-catalyzed peroxidation of linoleic acid, in w/c microemulsions stabilized by a fluorinated two-chained sulfosuccinate surfactant (di-HCF4). The activity of both enzymes in the w/c microemulsion environment was found to be essentially equivalent to that in a water/heptane microemulsion stabilized by Aerosol OT, a surfactant with the same headgroup as di-HCF4. The buffer 2-(A-morpholino)ethanesulfonic acid (MES) was used to fix the pH in the range 5-6. 

Tripeptide Ser-His-Asp had been introduced to the CD for simulating the chymotrypsin by the following method. Mix 2-amino ethyl mercaptan salts, 6-0-tosyl-/3-CD and NH4HCO3 with DMF/H2O (1 3) solution under nitrogen protection at 60 C for 4h. After vacuum concentration, separate the product by Sephadex G-10 column. The yield is about 43%. Mix the above product with Boc-Ser (Ot-Bu) -His-Asp (Ot-Bu) OH, dicyclohexyl carbodiimide, 1-hydroxy triazole in DMF solution to obtain 6-[Boc-Ser (Ot-Bu) -His-Asp (Ot-Bu) NHCH2CH2S]-/3-CD. Then treat with the TFA/CH2C12(9 1) mixed solution, vacuum concentrate and freeze-dry. This modified CD can be used as an analogue enzyme to hydrolyze nitrophenol esters. 

Predict which acid has a lower pH (is more acidic), /netfl-nitrophenol ot phenol, (circle one)... 

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