Synthesis of optically active methyl 1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylates having a halogen or an oxygen functional group at the 3a-position

A simple and new method for the preparation of optically active methyl 3a-chloro-, 3a-bromo-, 3a-hydroxy-, and 3a-alkoxy-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylates has been developed. © 2006 The Japan Institute of Heterocyclic Chemistry All rights reserved

Syntheses of optically active methyl 1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylates having a halogen or an oxygen functional group at the 3a-position

金沢大学大学院自然科学研究科生理活性物質科学金沢大学薬学部A simple and new method for the preparation of optically active methyl 3a-chloro-, 3a-bromo-, 3a-hydroxy-, and 3a-alkoxy-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-2-carboxylates has been developed. © 2006 The Japan Institute of Heterocyclic Chemistry All rights reserved

Different combinations of Notch ligands and receptors regulate V2 interneuron progenitor proliferation and V2a/V2b cell fate determination

[[abstract]]The broad diversity of neurons is vital to neuronal functions. During vertebrate development, the spinal cord is a site of sensory and motor tasks coordinated by interneurons and ongoing neurogenesis. In the spinal cord, V2-interneuron (V2-IN) progenitors (p2) develop into excitatory V2a-INs and inhibitory V2b-INs. The balance of these two types of interneurons requires precise control in the number and timing of their production. Here, using zebrafish embryos with altered Notch signaling, we show that different combinations of Notch ligands and receptors regulate two functions: the maintenance of p2 progenitor cells and the V2a/V2b cell fate decision in V2-IN development. Two ligands, DeltaA and DeltaD, and three receptors, Notch1a, Notch1b, and Notch3 redundantly contribute to p2 progenitor maintenance. On the other hand, DeltaA, DeltaC, and Notch1a mainly contribute to the V2a/V2b cell fate determination. A ubiquitin ligase Mib, which activates Notch ligands, acts in both functions through its activation of DeltaA, DeltaC, and DeltaD. Moreover, p2 progenitor maintenance and V2a/V2b fate determination are not distinct temporal processes, but occur within the same time frame during development. In conclusion, V2-IN cell progenitor proliferation and V2a/V2b cell fate determination involve signaling through different sets of Notch ligand-receptor combinations that occur concurrently during development in zebrafish