TsrM 是一种 B 12依赖性自由基 SAM 酶,可催化从碳原子到亲核原子的甲基化反应,使其成为一种独特且用途广泛的烷化剂。TsrM 能够直接转移吲哚环反应性较低的碳原子上的甲基,并在其底物上安装几个甲基。因此,通过显着催化非自由基反应,TsrM 在自由基 SAM 酶中具有独特的特性。(SAM:S-腺苷-L-蛋氨酸)。
Stereoselective Synthesis of Chiral Polycyclic Indolic Architectures through Pd<sup>0</sup>-Catalyzed Tandem Deprotection/Cyclization of Tetrahydro-β-carbolines on Allenes
作者:Valérian Gobé、Xavier Guinchard
DOI:10.1002/chem.201500273
日期:2015.6.1
Enantioenriched N‐allyl tetrahydro‐β‐carbolines were prepared by chiral phosphoric acid‐catalyzed Pictet–Spengler reactions. The compounds undergo Pd0‐catalyzed cyclizationsthrough a tandemdeprotection/cyclization process. The regioselectivity of the attack is controlled by the chain length and by the substitution pattern of the allene function. Products resulting from 5‐exo‐ or 6‐exo‐attack were obtained
通过手性磷酸催化的Pictet-Spengler反应制备了对映体富集的N-烯丙基四氢-β-咔啉。这些化合物通过串联的脱保护/环化过程经历Pd 0催化的环化。攻击的区域选择性由链长和丙二烯官能团的取代模式控制。从5 exo-或6 exo-攻击获得的产物的非对映异构体比例高达95:5。Azepinopyrrido [3,4 b ]吲哚通过7-获得内切-cyclizations。
Self-Relay Gold(I)-Catalyzed Pictet-Spengler/Cyclization Cascade Reaction for the Rapid Elaboration of Pentacyclic Indole Derivatives
Gold‐catalyzed cascadereactions allow the rapidelaboration of pentacyclic indolo[2,3‐a]quinolizidines from N‐allyl tryptamines and ortho‐alkynylarylaldehydes. The tandem process combines a gold‐catalyzed Pictet‐Spengler reaction and a cyclization occurring concomitantly with an allyl transfer from the nitrogen atom to the stilbene function. Various substituted allyls were successfully transferred
金催化的级联反应可快速合成N-烯丙基色胺和邻炔基芳基醛中的五环吲哚[2,3- a ]喹唑烷。串联过程结合了金催化的Pictet-Spengler反应和伴随从氮原子到二苯乙烯官能团的烯丙基转移而发生的环化反应。成功地转移了各种取代的烯丙基,从而提供了高非对映选择性的典型产物,产率为60-98%。带有丁烯醇链的色胺在高非对映选择性下会进一步环化成手性半胱氨酸。
Synthesis of Spiroindolenines via Regioselective Gold(I)-Catalyzed Cyclizations of <i>N</i>
-Propargyl Tryptamines
N-Propargyl tryptamines bearing N-substituents such as propargyl, allyl, alkyl or benzyl groups undergo regioselective gold-catalyzed cyclizations to the corresponding spiroindolenines, while it was previously shown that N-sulfonyl-N-propargyl tryptamines lead to achiral azepino[4,5-b]indoles. An asymmetric approach to these spiroindolenines is disclosed using chiral gold complexes, leading to enantiomeric
Ñ -Propargyl色胺轴承ñ -取代基如炔丙基,烯丙基,烷基或苄基团经历区域选择性金催化的环化反应,以相应的spiroindolenines,而先前被显示Ñ -sulfonyl- Ñ -propargyl色胺导致的非手性氮杂并[4, 5- b ]吲哚。使用手性金络合物公开了对这些螺环吲哚胺的不对称方法,导致对映体比率高达84/16。可以使用惠斯根环化,钯催化的交叉偶联或还原将螺环吲哚啉后期官能化。计算研究表明,取决于胺上取代基的性质,反应是通过不同的机理途径进行的。
Dissecting the Gold(I)-Catalyzed Carboaminations of <i>N</i>-Allyl Tetrahydro-β-carbolines to Allenes
compounds, resulting from both ring closure and the transfer of the allylic group from the nitrogen to the carbon backbone. The final skeleton obtained depends on the nature of both the R2 group of the allene and the R3 group of the allylic residue. Mechanistic studies and DFT calculations allowed the determination of all the mechanistic pathways involved in these processes, stemming from a common intermediate
N‐Allyltetrahydro‐β‐carbolines bearing a pendant allene undergo unprecedented gold(I)‐catalyzed cyclizations proceeding with an allyl migration from the nitrogen to the allene moiety. The initial product of the gold‐catalyzed cyclization evolves either via isomerization or Cope rearrangement, leading to different scaffolds. Density function theory (DFT) calculations established that the allyl migration