四甲尿酸

四甲尿酸
Chemical structure of theacrine.
IUPAC名
1,3,7,9-Tetramethylpurine-2,6,8-trione
别名 1,3,7,9-Tetramethyluric acid; Temurin; Temorine; Tetramethyluric acid; Tetramethyl uric acid
识别
CAS号 2309-49-1  checkY
PubChem 75324
ChemSpider 67862
SMILES
 
  • CN1C2=C(N(C1=O)C)N(C(=O)N(C2=O)C)C
InChI
 
  • 1/C9H12N4O3/c1-10-5-6(11(2)8(10)15)12(3)9(16)13(4)7(5)14/h1-4H3
InChIKey QGDOQULISIQFHQ-UHFFFAOYAN
性质
化学式 C9H12N4O3
摩尔质量 224.22 g·mol−1
若非注明，所有数据均出自标准状态（25 ℃，100 kPa）下。
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四甲尿酸（Theacrine）全名是1,3,7,9-四甲基尿酸，是由古布阿蘇（英语：Cupuaçu）及茶树葉子上提煉的生物鹼[1][2]。四甲尿酸有抗炎性及镇痛的效果，其結構類似咖啡因，也會以類似的方式影響腺苷的信号[2][3]。一般認為在茶葉上，四甲尿酸是由三步驟的路徑，由咖啡因所合成[2]。

結構類似咖啡因

四甲尿酸很類似咖啡因，差異只有一個酮基，以及在9-碳上的甲基基團。

Caffeine vs Theacrine

安全性

临床实验显示，健康人类可以每日安全服用 300 mg 四甲尿酸持续 8 周，且不会产生习惯。[4]实验中未发现四甲尿酸具有咖啡因等其他兴奋剂的快速耐受现象。[4]

在动物实验中，四甲尿酸的LD50为 810 mg/kg，[5][4]高于咖啡因的 265 mg/kg。[6]

相關條目

參考資料

  1. ^ Zheng, XQ; Ye, CX; Kato, M; Crozier, A; Ashihara, H. Theacrine (1,3,7,9-tetramethyluric acid) synthesis in leaves of a Chinese tea, kucha (Camellia assamica var. Kucha). Phytochemistry. 2002, 60 (2): 129–34. PMID 12009315. doi:10.1016/s0031-9422(02)00086-9. 
  2. ^ 2.0 2.1 2.2 Feduccia, Allison A.; Wang, Yuanyuan; Simms, Jeffrey A.; Yi, Henry Y.; Li, Rui; Bjeldanes, Leonard; Ye, Chuangxing; Bartlett, Selena E. Locomotor activation by theacrine, a purine alkaloid structurally similar to caffeine: Involvement of adenosine and dopamine receptors. Pharmacology Biochemistry and Behavior. 2012, 102 (2): 241. doi:10.1016/j.pbb.2012.04.014. 
  3. ^ Wang, Yuanyuan; Yang, Xiaorong; Zheng, Xinqiang; Li, Jing; Ye, Chuangxing; Song, Xiaohong. Theacrine, a purine alkaloid with anti-inflammatory and analgesic activities. Fitoterapia. 2010, 81 (6): 627–31. PMID 20227468. doi:10.1016/j.fitote.2010.03.008. 
  4. ^ 4.0 4.1 4.2 Taylor L, Mumford P, Roberts M, Hayward S, Mullins J, Urbina S, Wilborn C. Safety of TeaCrine®, a non-habituating, naturally-occurring purine alkaloid over eight weeks of continuous use. Journal of the International Society of Sports Nutrition. 2016, 13: 2 [2016-05-14]. PMC 4711067 可免费查阅. PMID 26766930. doi:10.1186/s12970-016-0113-3. （原始内容存档于2016-06-04）.
    • These findings support the clinical safety and non-habituating neuro-energetic effects of TeaCrine® supplementation over 8 weeks of daily use (up to 300 mg/day). Moreover, there was no evidence of a tachyphylactic response that is typical of neuroactive agents such as caffeine and other stimulants.
    • Specifically, the acute toxicity for theacrine ingestion in mice has been previously reported [4] to be an LD50 of 810.6 mg/kg, which would equate to roughly 4.0 g for an individual weighing 76 kg.     
  5. ^ Wang Y, Yang X, Zheng X, Li J, Ye C, Song X. Theacrine, a purine alkaloid with anti-inflammatory and analgesic activities (PDF). Fitoterapia. 2010, 81 (6): 627–31 [2016-05-15]. PMID 20227468. doi:10.1016/j.fitote.2010.03.008. （原始内容存档 (PDF)于2017-09-01）. the result of the acute toxicity test showed that the LD(50) of theacrine was 810.6 mg/kg (769.5-858.0mg/kg). 
  6. ^ Warszawski D, Gorodischer R, Kaplanski J. Comparative toxicity of caffeine and aminophylline (theophylline ethylenediamine) in young and adult rats. Biology of the Neonate. 1978, 34 (1-2): 68–71. PMID 698326. doi:10.1159/000241107. In adult rats, the LD50 of caffeine and aminophylline was the same after 24 h and after 1 week of observation: caffeine 265 mg/kg