181423-71-2

Upstream product

• 681431-19-6 2-hydroxy-4,5-dimethoxyphenylboronic acid 
• 681431-25-4 2-bromo-1-(3,4-dimethoxyphenyl)-8,9-dimethoxy-5,6-dihydropyrrolo[2,1-a]isoquinoline-3-carboxylic acid ethyl ester 
• 519753-21-0 2-[1-(3,4-dimethoxyphenyl)-8,9-dimethoxy-5,6-dihydropyrrolo[2,1-a]isoquinolin-2-yl]-4,5-dimethoxyphenyl ethyl carbonate 
• 14382-86-6 2-benzyloxy-4,5-dimethoxy-benzaldehyde 
• 127572-59-2 4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester 
• 289507-36-4 2-(2-bromo-4,5-dimethoxyphenyl)ethyl alcohol 
• 433267-55-1 4-bromo-1H-pyrrole-2-carboxylic acid ethyl ester 
• 2859-78-1 4-Bromoveratrole 
• 122775-35-3 3,4-Dimethoxyphenylboronic acid 
• 2328-12-3 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline monohydrochloride 
• 1265221-56-4 C₁₅H₁₃NO₆ 
• 1265221-57-5 C₁₅H₁₂BrNO₆ 
• 1265221-58-6 C₂₅H₂₄BrNO₈ 
• 74-88-4 methyl iodide 

Relevant academic research and scientific papers

Scalable Total Syntheses of Some Natural and Unnatural Lamellarins: Application of a One-Pot Domino Process for Regioselective Access to the Central 1,2,4-Trisubstituted Pyrrole Core

Short and scalable total syntheses of lamellarin G trimethyl ether, lamellarin D trimethyl ether, lamellarin H, lamellarin ?, dihydrolamellarin ?, and lamellarin U have been realized in four to six linear steps with an overall yield of ≤22%. Highlights of

Application of differential reactivity towards synthesis of lamellarin and 8-oxoprotoberberine derivatives: Study of photochemical properties of aryl-substituted benzofuran-8-oxoprotoberberines

A unique differential reactivity between dihydroisoquinolines and 3-nitrocoumarins was observed and was exploited for the efficient construction of lamellarins and their isomeric benzofuran-8-oxoprotoberberine derivatives under acid-catalyzed or base-promoted conditions. Further, these prepared aryl-substituted benzofuran-8-oxoprotoberberine derivatives bearing electron-donating substituents on benzofuran moiety are found to be benchtop stable but light-sensitive, and can undergo oxidative ring-opening reaction to give the corresponding keto products when exposed to visible light under aerobic conditions.

Synthesis of Lamellarin G Trimethyl Ether by von Miller–Pl?chl-Type Cyclocondensation

A concise synthesis of lamellarin G trimethyl ether based on a von Miller–Pl?chl-type cyclocondensation of a deprotonated α-amino nitrile with an α,β-unsaturated ketone as the key step was developed. The general strategy does not rely on molecular symmetry and allows for the independent variation of the substitution pattern.

Acid-Mediated Intermolecular [3 + 2] Cycloaddition toward Pyrrolo[2,1-a]isoquinolines: Total Synthesis of the Lamellarin Core and Lamellarin G Trimethyl Ether

A novel one-pot reaction has been developed for the efficient synthesis of pyrrolo[2,1-a]isoquinolines and 1-dearyllamellarin core from (E)-(2-nitrovinyl)benzenes and azomethine ylides generated in situ. This strategy provides a concise total synthesis of

A high-yielding modular access to the lamellarins: Synthesis of lamellarin G trimethyl ether, lamellarin η and dihydrolamellarin η

A deprotonated α-aminonitrile serves as a key intermediate in a highly efficient (95 % per step on average; see scheme) modular synthetic approach to the lamellarin alkaloids. Its reaction with an α,β- unsaturated aldehyde forms the central pyrrole ring in a one-pot procedure. The construction of the fused pentacyclic skeleton is completed by a microwave-assisted Ullmann-type lactone formation.

Lamellarins as inhibitors of P-glycoprotein-mediated multidrug resistance in a human colon cancer cell line

Chemical analysis of a Didemnum sp. (CMB-01656) collected during scientific Scuba operations off Wasp Island, New South Wales, yielded five new lamellarins A1 (1), A2 (2), A3 (3), A4 (4) and A5 (5) and eight known lamellarins C (6), E (7), K (8), M (9), S (10), T (11), X (12) and χ (13). Analysis of a second Didemnum sp. (CMB-02127) collected during scientific trawling operations along the Northern Rottnest Shelf, Western Australia, yielded the new lamellarin A6 (14) and two known lamellarins G (15) and Z (16). Structures were assigned to 1-16 on the basis of detailed spectroscopic analysis with comparison to literature data and authentic samples. Access to this unique library of natural lamellarins (1-16) provided a rare opportunity for structure-activity relationship (SAR) investigations, probing interactions between lamellarins and the ABC transporter efflux pump P-glycoprotein (P-gp) with a view to reversing multidrug resistance in a human colon cancer cell line (SW620 Ad300). These SAR studies, which were expanded to include the permethylated lamellarin derivative (17) and a series of lamellarin-inspired synthetic coumarins (19-24) and isoquinolines (25-26), successfully revealed 17 as a promising new non-cytotoxic P-gp inhibitor pharmacophore. Copyright

Modular total syntheses of lamellarin G trimethyl ether and lamellarin S

Modular total syntheses of the title compounds 2 and 3 are reported. The key pyrrolic building block 8 was prepared from the readily accessible pyrrole 6 via a di-iodination/mono-deiodination sequence. Suzuki-Miyaura cross-coupling of compound 8 with boronate ester 9 afforded lactone 10. Bromination of compound 10 followed by N-alkylation under Mitsunobu conditions afforded the fully substituted pyrrole 13 that engaged in a second Suzuki-Miyaura cross-coupling reaction with boronic acid 14 to give compound 15. Hydrolysis of the ester moiety within the last compound afforded acid 16 that engaged in a decarboxylative Heck cyclization process to give lamellarin G trimethyl ether (3). A related sequence of reactions starting from building block 8 and using the isopropoxy-substituted arenes 22, 25 and 27 has allowed for the completion of the first total synthesis of lamellarin S (2). The first total synthesis of the marine alkaloid lamellarin S is described.

Modular total synthesis of lamellarin G trimethyl ether

A modular synthesis of the lamellarin G trimethyl ether has been developed based on the application of several reaction sequences which include Friedel-Crafts acylation, esterification, haloarylation, and oxidative cyclization. The formation of pyrrolo [2

Synthesis of lamellarin U and lamellarin G trimethyl ether by alkylation of a deprotonated α-aminonitrile

(Chemical Equation Presented) 1,2,3,4-Tetrahydroisoquinoline-1- carbonitriles can serve as starting materials for the one-pot synthesis of 5,6-dihydropyrrolo[2,1a]isoquinolines and 1-benzyl-3,4-dihydroisoquinolines. The latter compounds were transformed to lamellarin G trimethyl ether and lamellarin U in short reaction sequences. This method allows the introduction of acid-sensitive protecting groups for the phenolic hydroxy functions which would be cleaved under the harsh conditions of the classical Bischler-Napieralski reaction.

Total synthesis of natural and unnatural lamellarins with saturated and unsaturated D-rings

(Chemical Equation Presented) Twenty-eight natural and unnatural lamellarins with either a saturated or an unsaturated D-ring were synthesized according to our developed synthetic route. The key step involved the Michael addition/ring closure (Mi-RC) of the benzyldihydroisoquinoline and α-nitrocinnamate derivatives, which provided the 2-carboethoxypyrrole intermediates in moderate to good yields (up to 78% yield). Subsequent hydrogenolysis/lactonization furnished lamellarins with a saturated D-ring in excellent yields (up to 93% yield). DDQ oxidation of the saturated lamellarin acetates led directly to the corresponding unsaturated analogues in 54-95% yield. In addition, only two steps in our developed strategy require column chromatography.