Disconnection Approach Research Articles

ChemInform Abstract: C-Terminal Anthranoyl-Anthranilic Acid Derivatives and Their Evaluation on CCK Receptors.

A series of C-terminal anthranoyl-anthranilic acid derivatives arising from a strict bond disconnection approach of asperlicin were synthesized and examined for their CCK receptor affinities. These compounds represent the second step of our investigation directed toward the search for alternative substructures of asperlicin as a starting point for the development of a new class of CCK ligands. The obtained micromolar affinities for CCK-A rather than CCK-B receptor confirm that the anthranilic acid dimer represents a useful template for the development of selective CCK-A receptor ligands.

C-terminal anthranoyl–anthranilic acid derivatives and their evaluation on CCK receptors

A series of C-terminal anthranoyl–anthranilic acid derivatives arising from a strict bond disconnection approach of asperlicin were synthesized and examined for their CCK receptor affinities. These compounds represent the second step of our investigation directed toward the search for alternative substructures of asperlicin as a starting point for the development of a new class of CCK ligands. The obtained micromolar affinities for CCK-A rather than CCK-B receptor confirm that the anthranilic acid dimer represents a useful template for the development of selective CCK-A receptor ligands.

Synthesis of Oncinotin‐11‐one, a Macrocyclic Polyamine Alkaloid from Oncinotis tenuiloba

AbstractThis paper presents a short synthesis of oncinotin‐11‐one (11), a minor alkaloid of Oncinotis tenuiloba (Apocynaceae). Based on a disconnection approach, the spermidine portion of the key intermediate 6 was constructed consecutively by simple N‐alkylations starting from ethyl piperidine‐2‐carboxylate (1). Treatment of 6 with in situ lithiated 2‐[(10‐bromodecyl)oxy]tetrahydropyran resulted in the formation of the keto moiety under simultanous deprotection of the lactam N‐atom to give the amino ketone 7 in 71% yield. Cleavage of the tetrahydro‐2H‐pyran‐2‐yl(Thp) portion and Jones oxidation of the resulting alcohol 8 gave the amino acid 9 which was cyclized. Final N‐debenzylation of 10 provided the natural alkaloid 11. Only two protective groups were needed in this synthesis. The reaction of N‐alkyl‐lactams with organometallic reagents is discussed.

The Convergent Route to Globular Dendritic Macromolecules: A Versatile Approach to Precisely Functionauzed Three-Dimensional Polymers and Novel Block Copolymers

The convergent growth approach to dendritic macromolecules is a versatile method for the preparation of globular molecules with highly controlled three-dimensional architectures. The method, inspired from a classical organic disconnection approach, starts growth of the globular dendrimer at what will become its chain-ends and proceeds toward what will become its center. The convergent growth has been applied to the preparation of a number of unconventional dendritic block copolymers as well as hybrid globular-linear copolymers that are not readily accessed by other routes. Control of the chemistry and the precise location of the chain-ends in convergent dendrimers is essential for the preparation of micellar, amphiphilic, dipolar, or other structures that may be useful in applications as varied as drug delivery and molecular devices.

A quick robust method for assigning a Kekulé structure

Abstract An algorithm for assigning a valid Kekule distribution of double bonds to a structure is delineated. Working by an ordered fragmentation and disconnection approach, the algorithm is fast and can be applied successfully to very complicated polyaromatic structures.

Organic Synthesis: The Disconnection Approach (Warren, Stuart)

Textbook for an introductory course in organic synthesis for graduate students and senior undergraduates.