138129-23-4

Upstream product

• 157097-00-2 2'-bromo-5'-trifluoromethyl-2-chloroacetanilide 
• 25947-13-1 ethyl 1,2-dihydro-1-oxophthalazin-4-ylacetate 

Downstream Products

• 138129-44-9 3-[2-[N-[2-Bromo-5-(trifluoromethyl)-phenyl]amino]-2-thioxoethyl]-3, 4-dihydro-4-oxo-1-phthalazinacetic acid 
• 138129-37-0 3-[2-[N-[2-Bromo-5-(trifluoromethyl)-phenyl]amino]-2-oxoethyl]-3, 4-dihydro-4-oxo-1-phthalazineacetic acid 
• 138129-28-9 3-[2-[N-[2-Bromo-5-(trifluoromethyl)phenyl]amino]2-thioxoethyl]-3, 4-dihydro-4-oxo-1-phthalazineacetic acid ethyl ester 

Relevant academic research and scientific papers

SUBSTITUTED OXOPHTHALAZINYL ACETIC ACIDS AND ANALOGS THEREOF

A compound of the formula wherein A1 and A2 are independently N or CH; B is a covalent bond or C=O; R1 is hydrogen or C1-C6 alkyl; R2 is hydrogen, fluorine, chlorine, bromine, trifluoromethyl, C1-C4 alkyl, C1-C4 alkoxy, or C1-C4 alkylthio; R3 is wherein R

Potent, orally active aldose reductase inhibitors related to zopolrestat: Surrogates for benzothiazole side chain

A broad structure-activity program was undertaken in search of effective surrogates for the key benzothiazole side chain of the potent aldose reductase inhibitor, zopolrestat (1). A structure-driven approach was pursued, which spanned exploration of three areas: (1) 5/6 fused heterocycles such as benzoxazole, benzothiophene, benzofuran, and imidazopyridine; (2) 5- membered heterocycles, including oxadiazole, oxazole, thiazole, and thiadiazole, with pendant aryl groups, and (3) thioanilide as a formal equivalent of benzothiazole. Several benzoxazole- and 1,2,4-oxadiazole- derived analogues were found to be potent inhibitors of aldose reductase from human placenta and were orally active in preventing sorbitol accumulation in rat sciatic nerve, in an acute test of diabetic complications. 3,4-Dihydro-4- oxo-3-[(5,7-difluoro-2-benzoxazolyl)methyl]-1-phthalazineacetic acid (124) was the best of the benzoxazole series (IC50 = 3.2 x 10-9 M); it suppressed accumulation of sorbitol in rat sciatic nerve by 78% at an oral dose of 10 mg/kg. Compound 139, 3,4-dihydro-4-oxo-3-[[(2-fluorophenyl)-1,2,4- oxadiazol-5-yl]methyl]-1-phthalazineacetic acid, with IC50 -8 M, caused a 69% reduction in sorbitol accumulation in rat sciatic nerve at an oral dose of 25 mg/kg. The thioanilide side chain featured in 3-[2-[[3- (trifluoromethyl)phenyl]amino]-2-thioxoethyl]-3,4-dihydro-4-oxo-1- phthalazineacetic acid (195) proved to be an effective surrogate for benzothiazole. Compound 195 was highly potent in vitro (IC50 = 5.2 x 10-8 M) but did not show oral activity when tested at 100 mg/kg. Additional structure-activity relationships encompassing a variety of heterocyclic side chains are discussed.

Novel, potent aldose reductase inhibitors: 3,4-dihydro-4-oxo-3-[[5-(trifluoromethyl)-2-benzothiazolyl]methyl]-1- phthalazineacetic acid (zopolrestat) and congeners

A new working hypothesis that there is a hitherto unrecognized binding site on the aldose reductase (AR) enzyme with strong affinity for benzothiazoles was pursued for the design of novel, potent aldose reductase inhibitors (ARIs). The first application of this hypothesis led to a novel series of 3,4-dihydro-4-oxo-3-(benzothiazolylmethyl)-1-phthalazineacetic acids. The parent of this series (207) was a potent inhibitor of AR from human placenta (IC50 = 1.9 x 10-8 M) and was orally active in preventing sorbitol accumulation in rat sciatic nerve, in an acute test of diabetic complications (ED50 = 18.5 mg/kg). Optimization of this lead through medicinal chemical rationale, including analogy from other drug series, led to more potent congeners of 207 and culminated in the design of 3,4-dihydro-4-oxo-3-[[5-(trifluoromethyl)-2-benzothiazolyl]methyl]-1- phthalazineacetic acid (216, CP-73,850, zopolrestat). Zopolrestat was found to be more potent than 207, both in vitro and in vivo. Its IC50 against AR and ED50 in the acute test were 3.1 x 10-9 M and 3.6 mg/kg, respectively. Its ED50s in reversing already elevated sorbitol accumulation in rat sciatic nerve, retina, and lens in a chronic test were 1.9, 17.6, and 18.4 mg/kg, respectively. It was well absorbed in diabetic patients, resulting in high blood level, showed a highly favorable plasma half-life (27.5 h), and is undergoing further clinical evaluation. An assortment of synthetic methods used for the construction of benzothiazoles, including an efficient synthesis of zopolrestat, is described. Structure-activity relationships in the new series are discussed.