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Showing 1 to 12 of 12 for “"Pictet-Spengler reaction"”.
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Synthetic Studies in the Formation of Nitrogen Containing Compounds: From Simple Amines to Complex Natural Products
… a ruthenium catalyzed ring-closing metathesis reaction. Utilizing Oppolzer's chiral auxiliary we could use this method to access enantioenriched free amino acids. Secondly we will discuss the progress toward the use of Frustrated Lewis pairs for the synthesis of chiral benzylic amines. …
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The Application of the Titanium-Catalyzed Hydroamination of Alkynes toward the Synthesis of Benzylisoquinoline Derivatives
… iodide 115 and alkyne 121 using a Sonogashira reaction. Dihydroisoquinoline 124 was obtained by intramolecular hydroamination of the aminoalkyne 123. Employing Noyori´s reduction protocol, the absolute configuration at C-1 of the benzylisoquinoline was introduced with 93% ee. Finally, …
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Synthetic studies of ecteinascidin 743 and fennebricin B
… of the natural product in 2008, featuring the Pictet-Spengler reaction to construct the pentacyclic core of Et-743. Our work, however, also produced both desired and undesired pentacycle without selectivity. We herein described an improved formal synthesis of Et-743 employing bromine auxiliary …
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Synthesis of the Antimalarial Flindersial Alkaloids
… readily available materials. The development of reaction conditions for the dimerization of borrerine in the presence of acid is discussed in detail. The progress toward the enantioselective total synthesis of flinderoles A, B, and C is also presented. The retrosynthetic plan was inspired by the …
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Exploiting alkaloid biosynthesis in Madagascar periwinkle to obtain natural product derivatives and new biocatalysts
… a biocatalyst, since it catalyzes the asymmetric Pictet- Spengler reaction to form tetrahydro-p-carboline pharmacophores. I used computer modeling to propose a model for how strictosidine synthase achieves its high stereoselectivity; this model may be used to engineer a Pictet-Spenglerase that …
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Crystallization studies of Pictet-Spenglerases
… synthase catalyzes the first committed reaction. This reaction is a Pictet-Spengler coupling between tryptamine and secologanin and produces the biosynthetic intermediate strictosidine, common to all monoterpene indole alkaloids. To better understand the structural features that impart …
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A Drug Discovery Study: Inhibitor Design for HRV 3C Protease Based on the Scaffold of (-)-Thysanone
… approach for 7-deoxy analogues using an oxa-Pictet-Spengler reaction in the key step. This oxa-Pictet-Spengler approach was also used for development of a new synthetic strategy for thysanone also involving C-H activation chemistry.
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Discovery, characterization, and rational design of the enzymes involved in monoterpene indole alkaloid biosynthesis in Madagascar periwinkle
… is strictosidine, the product of an asymmetric Pictet- Spengler condensation of tryptamine and the iridoid monoterpene secologanin. This reaction is catalyzed by the enzyme strictosidine synthase. This thesis describes the use of kinetic isotope effects, the rate dependence on pH, as well as …
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Chemical studies of metabolites from Pacific Ocean marine sponges and the starfish Dermasterias imbricata
… imbricatine (3) was accomplished using a Pictet-Spengler reaction to couple the starting materials 3-(3,5-dihydroxyphenyl) alanine methyl ester (143) and sodium 3-(4-benzyloxyphenyl) glycidate (141). A series of deprotections and protections on the resulting racemic …
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Hit to Lead Stage Optimization of Orally Efficacious β-Carboline Antimalarials
… of compound TCMDC-140230 was accomplished via Pictet-Spengler reaction of (S)- and (R)-7-methyl tryptophan methyl ester and 3,4-dichlorobenzaldehyde. The individual stereoisomeric esters were converted to the corresponding amides, but none of the stereoisomers of TCMDC-140230 were potent …
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Further Exploring the Structure Activity Relationship (SAR) of MMV008138 and MMV1803522
The war between human and malaria has never stopped, and the development and application of antimalarial drugs has not eradicated this terrible disease. To fight drug-resistant malaria, many leads have been studied over the years. (1S,3R)-MMV008138 and MMV1803522 are two compounds that have been …
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1,3-Disubstituted-tetrahydro-β-carbolines: A New Method for Stereochemical Assignment and Synthesis of Potential Antimalarial Agents
Malaria is a serious mosquito-borne disease affecting the majority of Earth's southern hemisphere. While consistent efforts to curb malaria spread throughout 20th and early 21st century were largely successful, the recent rise in resistance to antimalarial treatments resulted in an increasing …