Straightforward Synthesis of Functionalized 4,5,6,7-Tetrahydro-pyrazolo[1,5-a]pyrazines-Important Building Blocks for Medicinal Chemistry was written by Bozhanov, Vladimir I.;Bohdan, Dmytro P.;Borysov, Oleksandr V.;Silin, Aleksey V.;Zaremba, Oleg V.;Avramenko, Mykola M.;Volochnyuk, Dmitriy M.;Ryabukhin, Sergey V.;Gavrilenko, Konstantin S.. And the article was included in ChemistrySelect in 2022.Reference of 1314920-48-3 The following contents are mentioned in the article:
A set of building blocks based on the 4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine e.g., I scaffold is synthesized in a multigram scale in a cost-efficient manner. The possibility of the introduction of different substituents, neutral or functionalized in different positions of pyrazole and/or piperazine rings, is shown. The efficacy of using NH-pyrazole carbonic acids as a key intermediate of the process is demonstrated. The regioselectivity for direct insertion of the substituent to the 4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine core is discussed. The synthetic perspectives for using the functionalized 4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine as a bifunctional scaffold is discussed. The utilizing of building blocks obtained for the different region- and/or stereoselective synthesis, including sole transformations or modifications of functional groups, is demonstrated. The advantages of the proposed approach are proven compared with the other known methodologies. This study involved multiple reactions and reactants, such as 2-Methylpyrazolo[1,5-a]pyrazin-4(5H)-one (cas: 1314920-48-3Reference of 1314920-48-3).
2-Methylpyrazolo[1,5-a]pyrazin-4(5H)-one (cas: 1314920-48-3) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Reference of 1314920-48-3