26251-92-3

Upstream product

• 109704-79-2 N^b-benzyl-21-hydroxy-D-seco-Ψ-vincadifformine 
• 109704-80-5 N^b-benzyl-21-(tosyloxy)-D-seco-Ψ-vincadifformine 
• 139133-14-5 11α/β-<4-ξ-(1,3-dioxolan-2-yl)-1-hexyl>-1,2,4,6-tetrahydro-3,10b-methanoazepino<4,5-b>indole-5-carboxylate 
• 139133-17-8 (3aS,4R,11bR)-4-(2-[1,3]Dioxolan-2-yl-butyl)-2,3,3a,4,5,7-hexahydro-1H-pyrrolo[2,3-d]carbazole-6-carboxylic acid methyl ester 
• 139133-11-2 methyl (3aRS,4SR)-3-benzyl-2,3,3a,4,5,7-hexahydro-4-<2-ξ-(1,3-dioxolan-2-yl)-1-butyl>-1H-pyrrolo<2,3-d>carbazole-6-carboxylate 
• 136851-17-7 methyl 4-(1,3-dioxolan-2-yl)hexanoate 
• 139133-13-4 4-(1,3-dioxolan-2-yl)hexanal 
• 139133-21-4 4-(1,3-dioxolan-2-yl)-1-hexanol 
• 66757-48-0 methyl 4-formylhexanoate 
• 139133-18-9 D/E-trans-20,21-didehydro-Ψ-vincadifformine 
• 109704-78-1 2,16-Didehydro-16,20-bis(methoxycarbonyl)-21-phenyl-20,21-seco-pseudoaspidospermidine (3α,14β,20αβ) 
• 121074-32-6 (R)-4-[(S)-2-(Toluene-4-sulfonyloxymethyl)-butyl]-2,3,3a,4,5,7-hexahydro-1H-pyrrolo[2,3-d]carbazole-6-carboxylic acid methyl ester 

Relevant academic research and scientific papers

Synthesis of (-)-pseudotabersonine, (-)-pseudovincadifformine, and (+)-coronaridine enabled by photoredox catalysis in flow

Natural product modification with photoredox catalysis allows for mild, chemoselective access to a wide array of related structures in complex areas of chemical space, providing the possibility for novel structural motifs as well as useful quantities of less abundant congeners. While amine additives have been used extensively as stoichiometric electron donors for photocatalysis, the controlled modification of amine substrates through single-electron oxidation is ideal for the synthesis and modification of alkaloids. Here, we report the conversion of the amine (+)-catharanthine into the natural products (-)-pseudotabersonine, (-)-pseudovincadifformine, and (+)-coronaridine utilizing visible light photoredox catalysis.

Application of Ferrocenylalkyl Chiral Auxiliaries to Syntheses of Indolenine Alkaloids: Enantioselective Syntheses of Vincadifformine, ψ- And 20-epi-ψ-Vincadifformines, Tabersonine, Ibophyllidine, and Mossambine

Condensations of the chiral N-ferrocenylethylindoloazepines 4a,b, with the aldehydes 5, 13, 19, 29, and 32, led to tetracyclic vinylogous urethanes 6a,b and 7, 14a and 14b, 21a,c and 21b,d, 30a and 31a, and 30b and 31b. Respectively, 6:1, 5:1, 3:1, 1.7:1, and 2:1 diastereomeric selections provided intermediates which, on cleavage of the chiral auxiliary N-substituent and subsequent elaboration of ring D of the Aspidosperma and Strychnos alkaloids, provided enantiomerically pure (-)-ψ- and (-)-epi-ψ-vincadifformines (1, 2), (4-)-ibophyllidine (12), (+)- and (-)-vincadifformine (16a, 16b), (-)-tabersonine (27), and (-)-mossambine (41).

Synthesis of Vinca Alkaloids and Related Compounds. 64. Total Syntheses of (+/-)-Pseudovincadifformine and (+/-)-20-Epipseudovincadifformine

Using our previously reported convergent synthetic strategy, secondary amine 6 and aldehyde 9 reacted to give tetracyclic esters 10 and 11, which readily led to pentacyclic lactams 14-16.Selective reduction of these products gave (+/-)-pseudovincadifformine (4), (+/-)-20-epipseudovincadifformine (5), and (+/-)-14-epipseudovincadifformine (20).Aldehyde 23 was also prepared and could be directly used for synthesizing (+/-)-20-epipseudovincadifformine (5).The introduction of the double bond into ring D of the pseudoaspidospermane skeleton was successfully achieved to obtained 21-oxopseudotabersonine (30).

Syntheses of 20'-Deoxyvinblastine, 20'-Deoxyleurosidine, 20'-Deoxyvincovaline, 20'-epi-20'-Deoxyvincovaline, and 20'-Deoxyvincristine and Its 20'-Epimer through Racemic and Enantioselectively Generated Intermediates. New Syntheses of D/E-cis- and -trans-Ψ

Vindoline (20), on reaction with chloro imine derivatives of the D-seco-D/E-trans-Ψ- and -20-epi-Ψ-vincadifformines 18 and 19, followed by cyclization and debenzylation steps, provided the natural products 20'-deoxyvinblastine (4) and 20'-deoxyleurosidine