Flood, Aoife et al. published their research in European Journal of Medicinal Chemistry in 2017 | CAS: 70291-62-2

2-Amino-5,6-dihydro-4H-cyclopenta[b]thiophene-3-carbonitrile (cas: 70291-62-2) belongs to nitriles. The R-C-N bond angle in and nitrile is 180° which give a nitrile functional group a linear shape. Both the carbon and the nitrogen are sp hydridized which leaves them both with two p orbitals which overlap to form the two π bond in the triple bond. In conventional organic reductions, nitrile is reduced by treatment with lithium aluminium hydride to the amine. Reduction to the imine followed by hydrolysis to the aldehyde takes place in the Stephen aldehyde synthesis, which uses stannous chloride in acid.Reference of 70291-62-2

Thiophene/thiazole-benzene replacement on guanidine derivatives targeting α2-Adrenoceptors was written by Flood, Aoife;Trujillo, Cristina;Sanchez-Sanz, Goar;Kelly, Brendan;Muguruza, Carolina;Callado, Luis F.;Rozas, Isabel. And the article was included in European Journal of Medicinal Chemistry in 2017.Reference of 70291-62-2 This article mentions the following:

Searching for improved antagonists of α2-adrenoceptors, a thorough theor. study comparing the aromaticity of phenyl-, pyridinyl-, thiophenyl- and thiazolylguanidinium derivatives were carried out [at M06-2X/6-311++G(p,d) computational level] confirming that thiophene and thiazole were good ‘ring equivalent’ to benzene in these guanidinium systems. Based on these results, a small but chem. diverse library of guanidine derivatives were synthesized to explore the effect that the bioisosteric change has on affinity and activity at α2-adrenoceptors in comparison with our previously studied Ph derivatives All compounds were tested for their α2-adrenoceptor affinity and unsubstituted guanidinothiophenes displayed the strongest affinities in the same range as the Ph analogs. In the case of cycloalkyl systems, thiophenes with 6-membered rings showed the largest affinities, while for the thiazoles the 5-membered analog presented the strongest affinity. From all the compounds tested for noradrenergic activity, only one compound exhibited agonistic activity, while two compounds showed very promising antagonism of α2-adrenoceptors. In the experiment, the researchers used many compounds, for example, 2-Amino-5,6-dihydro-4H-cyclopenta[b]thiophene-3-carbonitrile (cas: 70291-62-2Reference of 70291-62-2).

2-Amino-5,6-dihydro-4H-cyclopenta[b]thiophene-3-carbonitrile (cas: 70291-62-2) belongs to nitriles. The R-C-N bond angle in and nitrile is 180° which give a nitrile functional group a linear shape. Both the carbon and the nitrogen are sp hydridized which leaves them both with two p orbitals which overlap to form the two π bond in the triple bond. In conventional organic reductions, nitrile is reduced by treatment with lithium aluminium hydride to the amine. Reduction to the imine followed by hydrolysis to the aldehyde takes place in the Stephen aldehyde synthesis, which uses stannous chloride in acid.Reference of 70291-62-2

Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts