202579-59-7

Upstream product

• 13360-63-9 N-ethylbutylamine 
• 948553-53-5 7-chloro-3-(2,4-dichlorophenyl)-2,5-dimethylpyrazolo[1,5-a]pyrimidine 
• 214416-34-9 3-(2,4-Dichloro-phenyl)-2,5-dimethyl-4H-pyrazolo[1,5-a]pyrimidin-7-one 
• 214416-40-7 5-amino-4-(2,4-dichlorophenyl)-3-methylpyrazole 
• 76562-15-7 1-cyano-1-(2,4-dichlorophenyl)propan-2-one 
• 6306-60-1 2,4-Dichlorophenylacetonitrile 

Relevant academic research and scientific papers

Synthesis, F-18 radiolabeling, and microPET evaluation of 3-(2,4-dichlorophenyl)-N-alkyl-N-fluoroalkyl-2,5-dimethylpyrazolo[1,5-a]pyrimidin-7-amines as ligands of the corticotropin-releasing factor type-1 (CRF1) receptor

A series of 3-(2,4-dichlorophenyl)-N-alkyl-N-fluoroalkyl-2,5-dimethylpyrazolo[1,5-a]pyrimidin-7-amines were synthesized and evaluated as potential positron emission tomography (PET) tracers for the corticotropin-releasing factor type-1 (CRF1) receptor. Compounds 27, 28, 29, and 30 all displayed high binding affinity (≤1.2 nM) to the CRF1 receptor when assessed by in vitro competition binding assays at 23 °C, whereas a decrease in affinity (≥10-fold) was observed with compound 26. The log P7.4 values of [18F]26-[18F]29 were in the range of ～2.2-2.8 and microPET evaluation of [18F]26-[18F]29 in an anesthetized male cynomolgus monkey demonstrated brain penetrance, but specific binding was not sufficient enough to differentiate regions of high CRF1 receptor density from regions of low CRF1 receptor density. Radioactivity uptake in the skull, and sphenoid bone and/or sphenoid sinus during studies with [18F]28, [18F]28-d8, and [18F]29 was attributed to a combination of [18F]fluoride generated by metabolic defluorination of the radiotracer and binding of intact radiotracer to CRF1 receptors expressed on mast cells in the bone marrow. Uptake of [18F]26 and [18F]27 in the skull and sphenoid region was rapid but then steadily washed out which suggests that this behavior was the result of binding to CRF1 receptors expressed on mast cells in the bone marrow with no contribution from [18F]fluoride.

The discovery of 4-(3-pentylamino)-2,7-dimethyl-8-(2-methyl-4- methoxyphenyl)-pyrazolo-[1,5-a]-pyrimidine: A corticotropin-releasing factor (hCRF1) antagonist

Structure-activity relationship studies led to the discovery of 4-(3- pentylamino)-2,7-dimethyl-8-(2-methyl-4-methoxyphenyl)-pyrazolo-[1,5-a]- pyrimidine 11-31 (DMP904), whose pharmacological profile strongly supports the hypothesis that hCRF1 antagonists may be potent anxiolytic drugs. Compound 11-31 (hCRF1 K(i) = 1.0 ± 0.2 nM (n = 8)) was a potent antagonist of hCRF1-coupled adenylate cyclase activity in HEK293 cells (IC50 = 10.0 ± 0.01 nM versus 10 nM r/hCRF, n = 8); α-helical CRF(9-41) had weaker potency (IC50 = 286 ± 63 nM, n = 3). Analogue 11-31 had good oral activity in the rat situational anxiety test; the minimum effective dose for 11-31 was 0.3 mg/kg (po). Maximal efficacy (approximately 57% reduction in latency time in the dark compartment) was observed at this dose. Chlordiazepoxide caused a 72% reduction in latency at 20 mg/kg (po). The literature compound 1 (CP154526-1, 30 mg/kg (po)) was inactive in this test. Compound 11-31 did not inhibit open-field locomotor activity at 10, 30, and 100 mg/kg (po) in rats. In beagle dogs, this compound (5 mg/kg, iv, po) afforded good plasma levels. The key iv pharmacokinetic parameters were t(1/2), CL and V(d,ss) values equal to 46.4 ± 7.6 h, 0.49 ± 0.08 L/kg/h and 23.0 ± 4.2 L/kg, respectively. After oral dosing, the mean C(max), T(max), t(1/2) and bioavailability values were equal to 1260 ± 290 nM, 0.75 ± 0.25 h, 45.1 ± 10.2 h and 33.1%, respectively. The overall rat behavioral profile of this compound suggests that it may be an anxiolytic drug with a low motor side effect liability. (C) 2000 Elsevier Science Ltd.

Pyrazolo[1,5-a]pyrimidine CRF-1 receptor antagonists

A series of 3-phenylpyrazolo[1,5-a]pyrimidines was prepared and found to have affinity for the human CRF-1 receptor. The 3-dimensional structure of one of the most potent analogs in this series, 10d, was determined by X-ray crystallography and suggests the spatial requirements for potent CRF-1 receptor binding affinity in this series.