Stereoselective synthesis of Jaspine B and its C2 epimer from Garner aldehyde
作者:Amit Kumar Jana、Gautam Panda
DOI:10.1039/c3ra41778f
日期:——
Two different stereoselective routes for the synthesis of Jaspine B and its C2 epimer are presented here, starting from easily available Garneraldehyde. The key synthetic steps involved iodocyclization, organocuprate addition, HWE olefination, regioselective α-tosylation and cross metathesis reaction. This is the first report to synthesize Jaspine B involving iodocyclization.
Synthesis of pachastrissamine (jaspine B) and its derivatives by the late-stage introduction of the C-2 alkyl side-chains using olefin cross metathesis
An improved divergent synthesis of the four diastereomers of pachastrissamine from Garner's aldehyde has been reported. The common intermediate was synthesized by an indium-mediated acetoxyallylation reaction. The long alkyl sidechain was introduced in the late stage of the synthesis using an olefin cross metathesis reaction. Biologicalevaluation of the chain modified analogs of the (2S,3S,4R)-isomer
Substrate and stereocontrolled iodocycloetherification of highly functionalized enantiomerically pure allylic alcohols: application to synthesis of cytotoxic 2-epi jaspine B and its biological evaluation
作者:Somireddy Kundooru、Pintu Das、Sanjeev Meena、Vikash Kumar、Mohammad Imran Siddiqi、Dipak Datta、Arun K. Shaw
DOI:10.1039/c5ob01123j
日期:——
Stereoselectivities of electrophilic additions of molecular iodine to enantiomerically pure highly functionalized allylic alcohols with internal nucleophiles have been investigated. The intramolecular nucleophilic attack on the I2–π complex by an oxygen nucleophile to obtain tri- and tetrasubstituted THFs is highly regio-, stereoselective and substrate controlled. The application of this study has
Novel sphingosine-containing analogues selectively inhibit sphingosine kinase (SK) isozymes, induce SK1 proteasomal degradation and reduce DNA synthesis in human pulmonary arterial smooth muscle cells
作者:Hoe-Sup Byun、Susan Pyne、Neil MacRitchie、Nigel J. Pyne、Robert Bittman
DOI:10.1039/c3md00201b
日期:——
Sphingosine 1-phosphate (S1P) is involved in hyper-proliferative diseases such as cancer and pulmonary arterial hypertension. We have synthesized inhibitors that are selective for the two isoforms of sphingosine kinase (SK1 and SK2) that catalyze the synthesis of S1P. A thiourea adduct of sphinganine (F02) is selective for SK2 whereas the 1-deoxysphinganines 55-21 and 77-7 are selective for SK1. (2S,3R)-1-Deoxysphinganine (55-21) induced the proteasomal degradation of SK1 in human pulmonary arterial smooth muscle cells and inhibited DNA synthesis, while the more potent SK1 inhibitors PF-543 and VPC96091 failed to inhibit DNA synthesis. These findings indicate that moderate potency inhibitors such as 55-21 are likely to have utility in unraveling the functions of SK1 in inflammatory and hyperproliferative disorders.
Jaspine B and its C-2 and/or C3 epimers have been enantio-selectively prepared from butadiene monoepoxide through a synthetic procedure consisting of allylicamination by palladium-catalyzed dynamic kinetic asymmetric transformation, cross metathesis, and stereoselective dihydroxylation as key steps.
Jaspine B 及其 C-2 和/或 C3 差向异构体已经从丁二烯单环氧化物通过合成程序对映选择性制备,该合成程序包括通过钯催化的动态动力学不对称转化、交叉复分解和立体选择性二羟基化的烯丙基胺化作为关键步骤。