138713-73-2

Upstream product

• 87463-28-3 (Z)-hexa-3,5-dienyl p-toluenesulfonate 
• 100-46-9 benzylamine 
• 36206-73-2 (E)-hexa-3,5-dien-1-yl 4-methylbenzenesulfonate 

Downstream Products

• 138713-71-0 (4aS,7aS,10aR)-2-Benzyl-8,8-dimethyl-1,2,3,4,4a,7,7a,8,9,10-decahydro-pyrrolo[2,3-i]isoquinolin-8-ium; iodide 
• 138713-71-0 (4aR,7aS,10aR)-2-Benzyl-8,8-dimethyl-1,2,3,4,4a,7,7a,8,9,10-decahydro-pyrrolo[2,3-i]isoquinolin-8-ium; iodide 
• 138713-70-9 (4aS,7aS,10aS)-2-Benzyl-1-oxo-2,3,4,4a,7,7a,9,10-octahydro-1H-pyrrolo[2,3-i]isoquinoline-8-carboxylic acid ethyl ester 
• 138713-70-9 (4aR,7aS,10aS)-2-Benzyl-1-oxo-2,3,4,4a,7,7a,9,10-octahydro-1H-pyrrolo[2,3-i]isoquinoline-8-carboxylic acid ethyl ester 
• 138713-74-3 4-[N-benzyl-N-hexa-3'(Z),5'-dien-1'-yl]carbamoyl-2,3-dihydropyrrole-1-carboxylic acid ethyl ester 

Relevant academic research and scientific papers

Enantioselective total syntheses of manzamine A and related alkaloids

As a prelude to undertaking the total syntheses of the complex manzamine alkaloids, a series of model studies were conducted to establish the scope and limitations of intramolecular [4 + 2] cycloadditions of N-acylated vinylogous ureas with the trienic substrates 17a,b, 28a,b, and 34. These experiments clearly demonstrated that the geometry of the internal double bond and the presence of an electron-withdrawing group on the diene moiety were essential for the facile and stereoselective formation of the desired cycloadducts. The enantioselective syntheses of the manzamine alkaloids ircinol A (75), ircinal A (5), and manzamine A (1) were then completed by employing a convergent strategy that featured a novel domino Stille/Diels-Alder reaction to construct the tricyclic ABC ring core embodied in these alkaloids. Thus, the readily accessible chiral dihydropyrrole 58 was first converted in a single chemical operation into the key tricyclic intermediate 60. Two ring-closing metathesis reactions were then used to form the 13- and 8-membered rings leading to Z-72 and 74, the latter of which was quickly elaborated into ircinal A (5) via ircinol A (75). The synthetic 5 thus obtained was converted into manzamine A (1) following literature precedent. This concise synthesis of ircinal A required a total of 24 operations from commercially available starting materials with the longest linear sequence being 21 steps.

Construction of the tricyclic ABC ring subunit of manzamine A via a novel intramolecular Diels-Alder reaction

A novel entry to the manzamine A (1) has been designed that features an intramolecular Diels-Alder reaction of a vinylogous imide for the facile construction of the tricyclic core of 1 as illustrated by the conversions 8 and 16 → 9.