Extraction and analysis on the aromatic components of Pu-erh ripe tea and raw tea was written by Hong, Tao;Huang, Zun-xi;Li, Jun-jun;Tang, Xiang-hua;Mu, Yue-lin;Xu, Bo. And the article was included in Chaye Kexue in 2010.Name: 1-Ethyl-1H-pyrazol-5-amine This article mentions the following:
The aromatic components from Pu-erh ripe and raw tea which storage for different years extracted by methylene chloride and Et ether through vacuum distillation extraction, and then investigated by gas chromatog.-mass spectrometry. It showed that the aromatic compounds extracted by methylene chloride were more than Et ether no matter they were ripe tea or raw tea. Those compounds including hydrocarbons, heterocyclic oxygen compounds, nitrogenous compounds, ketones were extracted more by methylene chloride than those extracted by Et ether. However, more esters and phenolic compounds were extracted by Et ether. The contents of benzothiazole and caffeine increased during the process of ripe tea’s storage, but the contents of phthalic acid, iso-Bu octyl ester and 1,2,4-trimethoxybenzene were decreased. The contents of 5-amino-1-ethylpyrazole, N-phenyl-1-naphthalenamine, 1,2,3-trimethoxybenzene and phthalic acid-iso-butyl-octyl ester were increased during the storing process of raw tea, but the contents of trans-squalene, linalool, beta-iso-Me ionone and caffeine were decreased. At the same time, there were many aromatic compounds of heterocyclic oxygen compounds in ripe tea. The main components of these 10 heterocyclic oxygen compounds included 1,2,3-trimethoxybenzene. The contents of alcs. aromatic components in raw tea, such as 1-octen-3-yl, linalool, cyclohexanol, 2,6-dimethylcyclohexanol, Ph Et alc. and cedrol. In the experiment, the researchers used many compounds, for example, 1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3Name: 1-Ethyl-1H-pyrazol-5-amine).
1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3) belongs to pyrazole derivatives. Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. The presence of both electronegative nitrogen atoms in the pyrazole ring reduces the electron density of the C3- and C5-positions leaving electron density of C4-position unaltered. Thus the C4-position is vulnerable to electrophilic attack. The C3 electrophilic-position may undergo deprotonation in the presence of a strong base leading to ring opening.Name: 1-Ethyl-1H-pyrazol-5-amine
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics