Four new tetracyclic alkaloids with cis-decahydroquinoline motif from Myrioneuron effusum

Abstract

Four new Myrioneuron alkaloids, mysumamides A-D (1-4), along with three known ones were isolated from the twigs and leaves of Myrioneuron effusum. All of these alkaloids possessed the tetracyclic skeleton and contained the decahydroquinoline (cis-DHQ) moiety. Their structures and relative configurations were elucidated on the basis of spectroscopic methods, especially 2D NMR techniques. The absolute configuration of 1 was determined by single-crystal X-ray diffraction. The cytotoxic activities of these compounds were also evaluated in vitro.

Enantioselective total synthesis of (−)-myrifabral A and B

“…2 Since 2013, many new alkaloids have been isolated from Myrioneuron faberi, 3 Myrioneuron tonkinesis, 4 and Myrioneuron effusum. 5 In addition to their interesting structural features, a number of these alkaloids possess a range of biological activities such as antimalarial properties, KB cell cytotoxicity, antimicrobial, and hepatitis C virus (HCV) replication inhibition. [1][2][3][4][5] Despite possessing promising biological properties and synthetically attractive motifs, relatively few of these alkaloids have been prepared by total synthesis efforts.…”

“…5 In addition to their interesting structural features, a number of these alkaloids possess a range of biological activities such as antimalarial properties, KB cell cytotoxicity, antimicrobial, and hepatitis C virus (HCV) replication inhibition. [1][2][3][4][5] Despite possessing promising biological properties and synthetically attractive motifs, relatively few of these alkaloids have been prepared by total synthesis efforts. 2d,e,f,6 We became interested in (AE)-myrifabral A (4) and (AE)-myrifabral B (5) in particular due to their unique cyclohexane fused octahydroquinolizine skeletons which contain four contiguous stereogenic centers, including an all-carbon quaternary center embedded in the cyclohexane fusion.…”

“…[1][2][3][4][5] Despite possessing promising biological properties and synthetically attractive motifs, relatively few of these alkaloids have been prepared by total synthesis efforts. 2d,e,f,6 We became interested in (AE)-myrifabral A (4) and (AE)-myrifabral B (5) in particular due to their unique cyclohexane fused octahydroquinolizine skeletons which contain four contiguous stereogenic centers, including an all-carbon quaternary center embedded in the cyclohexane fusion. Interestingly, both 4 and 5 are isolated as racemic mixtures of aand b-hydroxy epimers.…”

Enantioselective Total Synthesis of (–)-Myrifabral A and B

“…2 Since 2013, many new alkaloids have been isolated from Myrioneuron faberi, 3 Myrioneuron tonkinesis, 4 and Myrioneuron effusum. 5 In addition to their interesting structural features, a number of of these alkaloids possess a range of biological activities such as antimalarial properties, KB cell cytotoxicity, antimicrobial, and hepatitis C virus (HCV) replication inhibition. [1][2][3][4][5] Despite possessing promising biological properties and synthetically attractive motifs, relatively few of these alkaloids have been prepared by total synthesis efforts.…”

“…We became interested in (±)-myrifabral A ( 4) and (±)myrifabral B (5) in particular due to their unique cyclohexane fused octahydroquinolizine skeletons which contain four contiguous stereogenic centers, including an all-carbon quaternary center embedded in the cyclohexane fusion. Interestingly, both 4 and 5 are isolated as racemic mixtures of aand b-hydroxy epimers.…”