5334-59-8Relevant academic research and scientific papers
New pyrazolopyrimidine derivatives as Leishmania amazonensis arginase inhibitors
Feitosa, Livia M.,da Silva, Edson R.,Hoelz, Lucas V.B.,Souza, Danielle L.,Come, Julio A.A.S.S.,Cardoso-Santos, Camila,Batista, Marcos M.,Soeiro, Maria de Nazare C.,Boechat,Pinheiro, Luiz C.S.
, p. 3061 - 3069 (2019/06/08)
Arginase performs the first enzymatic step in polyamine biosynthesis in Leishmania and represents a promising target for drug development. Polyamines in Leishmania are involved in trypanothione synthesis, which neutralize the oxidative burst of reactive oxygen species (ROS) and nitric oxide (NO) that are produced by host macrophages to kill the parasite. In an attempt to synthesize arginase inhibitors, six 1-phenyl-1H-pyrazolo[3,4-d]pyrimidine derivatives with different substituents at the 4-position of the phenyl group were synthesized. All compounds were initially tested at 100 μM concentration against Leishmania amazonensis ARG (LaARG), showing inhibitory activity ranging from 36 to 74%. Two compounds, 1 (R=H) and 6 (R=CF3), showed arginase inhibition >70% and IC50 values of 12 μM and 47 μM, respectively. Thus, the kinetics of LaARG inhibition were analyzed for compounds 1 and 6 and revealed that these compounds inhibit the enzyme by an uncompetitive mechanism, showing Kis values, and dissociation constants for ternary complex enzyme-substrate-inhibitor, of 8.5 ± 0.9 μM and 29 ± 5 μM, respectively. Additionally, the molecular docking studies proposed that these two uncompetitive inhibitors interact with different LaARG binding sites, where compound 1 forms more H-bond interactions with the enzyme than compound 6. These compounds showed low activity against L. amazonensis free amastigotes obtained from mice lesions when assayed with as much as 30 μM. The maximum growth inhibition reached was between 20 and 30% after 48 h of incubation. These results suggest that this system can be promising for the design of potential antileishmanial compounds.
Synthesis and anti-Plasmodium falciparum evaluation of novel pyrazolopyrimidine derivatives
Silveira, Flávia F.,Feitosa, Lívia M.,Mafra, Jo?o C. M.,Ferreira, Maria de Lourdes G.,Rogerio, Kamilla R.,Carvalho, Leonardo J. M.,Boechat, Nubia,Pinheiro, Luiz C. S.
, p. 1876 - 1884 (2018/06/25)
Nine 1-phenyl-1H-pyrazolo[3,4-d]pyrimidine derivatives with different substituents in the 4-position of the phenyl group and benzenesulfonamide moiety were synthesized and evaluated against Plasmodium falciparum. Six compounds exhibited activity in vitro against the chloroquine-resistant clone W2 with IC50 values ranging from 5.13 to 12.22 μM. The most active derivative with substituents R1 = F / R2 = CH3 exhibited an IC50 value of 5.13 μM and an IS value of 62.90, which was higher than that of the control drug sulfadoxine. For this reason, it is possible to conclude that the 1H-pyrazolo[3,4-d]pyrimidine system is promising as a prototype for further studies of antimalarial candidates.
Synthesis and in vitro antiproliferative activity of novel pyrazolo[3,4-d]pyrimidine derivatives
Abdou, Nermin S.,Serya, Rabah A. T.,Esmat, Ahmed,Tolba, Mai F.,Ismail, Nasser S. M.,Abouzid, Khaled A. M.
supporting information, p. 1518 - 1534 (2015/08/18)
A novel series of pyrazolo[3,4-d]pyrimidine derivatives were designed, synthesized and evaluated for their antiproliferative activity. Among the five compounds selected by NCI, compound 11a showed a distinctive pattern of selectivity on cell line panels and was further screened for a 5-log dose range, where it showed potent antiproliferative activity with median growth inhibition (GI50) equal to 1.71 μM against the CNS cancer SNB-75 cell line. The tested derivative showed remarkably the highest cell growth inhibition against non-small cell lung cancer HOP-62, CNS cancer SNB-75, breast cancer HS578T, and melanoma MALME-3M cell lines. Flow cytometric analysis revealed that compound 11a could significantly induce apoptosis in A549 cells in vitro at low micromolar concentrations. Further investigation showed that compound 11a induced significant cell cycle arrest at G0/G1 phase partly due to its ability to downregulate cyclin D1 and upregulate p27kip1 levels.
Synthesis of 1,4-disubstituted pyrazolo[3,4-d]pyrimidines from 4,6-dichloropyrimidine-5-carboxaldehyde: Insights into selectivity and reactivity
Morrill, Christie,Babu, Suresh,Almstead, Neilg.,Moon, Young-Choon
, p. 1791 - 1806 (2013/07/26)
Strategies for carrying out the reaction of 4,6-dichloropyrimidine-5- carboxaldehyde with both aromatic and aliphatic hydrazines to generate 1-substituted 4-chloropyrazolo[3,4-d]pyrimidines in a selective, high-yielding, and operationally simple manner are presented. For aromatic hydrazines, the reaction is performed at a high temperature in the absence of an external base. For aliphatic hydrazines, the reaction proceeds at room temperature in the presence of an external base. The observed selectivity and reactivity trends are rationalized through consideration of the proposed reaction mechanism. The 1-substituted 4-chloropyrazolo[3,4-d]pyrimidine products serve as versatile synthetic intermediates, through further functionalization of the 4-chloride moiety, enabling the rapid generation of a structurally diverse array of 1,4-disubstituted pyrazolo[3,4-d]pyrimidines. Georg Thieme Verlag Stuttgart. New York.
Selective synthesis of 1-substituted 4-chloropyrazolo[3,4-d]pyrimidines
Babu, Suresh,Morrill, Christie,Almstead, Neil G.,Moon, Young-Choon
supporting information, p. 1882 - 1885 (2013/06/05)
Strategies for carrying out the reaction of 4,6-dichloropyrimidine-5- carboxaldehyde with various hydrazines to generate 1-substituted 4-chloropyrazolo[3,4-d]pyrimidines in a selective and high-yielding manner are presented. For aromatic hydrazines, the reaction is performed in the absence of an external base, which promotes exclusive hydrazone formation. The hydrazones subsequently cyclize at an elevated temperature to form the desired pyrazolo[3,4-d]pyrimidine products. For aliphatic hydrazines, the reaction sequence proceeds as a single step in the presence of an external base.
PYRAZOLOPYRIMIDINES AS ANTI - HEPATITS C AGENTS
-
Page/Page column 26, (2010/02/11)
Pyrazolopyrimidine derivatives of formula (I), or a pharmaceutically acceptable salt thereof, are found to be active against hepatitis C infection, wherein: R1 is C6-C10 aryl, 5- to 10- membered heteroary1, -(C1-C4 alkyl)-(C6-C10 aryl) or -(C1-C4 alkyl)-(5- to 10- membered heteroaryl); R2 is a C6-C10 aryl, C3-C6 carbocyclyl, 5- to 10- membered heteroaryl or 5- to 10- membered heterocyclyl moiety, said moiety being optionally fused to a C6-C10 aryl, C3-C6 carbocyclyl, 5- to 10- membered heteroaryl or 5- to 10-membered heterocyclic ring; and X is -NR'-, -NR'-CO-NR''-, -NR'-L, or -NR'-CO-L-, wherein R' and R'' are the same or different and each represent hydrogen or a C1-C6 alkyl group and L represents a C1-C6 alkylene group, the aryl, heteroaryl, heterocyclyl. and carbocyclyl moieties in the R1 and R2 substituents being unsubstituted or substituted by 1, 2 or 3 substituents selected from halogen, C1-C4 alkyl C1-C4alkoxy, C1-C4 haloalkyl, C1-C4 haloalkoxy, cyano, nitro, C6-C10 aryl, C3-C6 carbocyclyl, 5- to 10- membered heterocyclyl, 5- to 10- membered heteroaryl, -NR'-CO2-R'', -CO2R'', -COR'''-NR'-CO-R''',-CONR'R'',SO2NR'R'',SO2R'''and -O-(CH2)n-R''' substituents, wherein n is from 0 to 4, each R’is the same or different and is hydrogen or C1-C6 alkyl, each R'' is the same or different and is hydrogen, C1-C6 alkyl, C6-C10 aryl, 5- to 10- membered heterocyclyl or 5- to 10- membered heteroaryl, each R''' is the same or different and is C1-C6 alkyl, C6-C10 aryl, 5- to 10- membered heterocyclyl or 5- to 10- membered heteroaryl, and each R'''' is the same or different and is C6-C10 aryl, 5- to 10- membered heterocyclyl or 5- to 10- membered heterocryl, the aryl, heteroaryl, heterocyclyl and carbocyclyl moieties in said substituents being unsubstituted or substituted by a further substituent selected from C1-C4 alkyl, C1-C4 hydroxyalkyl and C1-C4 haloalkyl groups.
