Synthese von Dibenzo[a,g]chinolizinen — Ein neuer Zugang zu Protoberberinen
摘要:
A novel synthesis to prepare dibenzo-8-quinolizinones 8 is reported using the intramolecular cyclisation of the benzylated Reissert compounds 6 for the key step. Methylation of 8 by methyllithium gives partial deoxygenated coralynes 10 which in turn can be reduced by NaBH4 yielding the 8-methyltetrahydro-protoberberines 11. The structures are assigned by NMR-spectroscopy.
Synthese von Dibenzo[a,g]chinolizinen — Ein neuer Zugang zu Protoberberinen
摘要:
A novel synthesis to prepare dibenzo-8-quinolizinones 8 is reported using the intramolecular cyclisation of the benzylated Reissert compounds 6 for the key step. Methylation of 8 by methyllithium gives partial deoxygenated coralynes 10 which in turn can be reduced by NaBH4 yielding the 8-methyltetrahydro-protoberberines 11. The structures are assigned by NMR-spectroscopy.
The present invention relates to neurologically-active compounds, being heterocyclic compounds having two fused 6-membered rings with a nitrogen atom at position 1 and a hydroxy or mercapto group at position 8 with at least one ring being aromatic. Also disclosed are processes for the preparation of these compounds and their use as pharmaceutical or veterinary agents, in particular for the treatment of neurological conditions, more specifically neurodegenerative conditions such as Alzheimer's disease.
The invention provides a compound of formula (I), or a salt or prodrug thereof, wherein R1, R4-R8, R10, R2'-R6', W, and A have any of the values described in the specification, as well as compositions comprising a compound of formula (I). The compounds are useful as antibacterial agents.
Pd-Catalyzed C(sp<sup>2</sup>)–H carbonylation of 2-benzylpyridines for the synthesis of pyridoisoquinolinones
作者:Zeqiang Xie、Shuang Luo、Qiang Zhu
DOI:10.1039/c6cc07612b
日期:——
An efficient synthesis of pyridoisoquinolinones, through Pd-catalyzed carbonylative annulation of 2-benzylpyridines, has been developed.
通过Pd催化的2-苄基吡啶的羰基环化反应,成功合成了吡啶异喹啉酮。
Reissert compound studies. XXXIX. A novel approach to the berbine and 6-azaberbine systems and related derivatives of ellipticine
作者:Seshadri Veeraraghavan、Frank D. Popp
DOI:10.1002/jhet.5570180115
日期:1981.1
indoloberbine ring skeletons is reported. Treatment of heterocyclicbases such as isoquinolines, phthalazines, and ellipticine with 2-chloromethylbenzoyl chloride and trimethylsilyl cyanide gave the corresponding Reissert compounds. Treatment of these Reissert compounds with sodium hydride resulted in intramolecular cyclization with loss of hydrogencyanide.
The annulation of isoquinoline derivatives to form the 8-oxoprotoberberine derivatives is described. The key step of the reaction involves intramolecular alkylation of the Reissertcompounds.