2. Essential Components: Earlier Developments 5449 2.1. Activated alkenes/alkynes 5450 2.1.1. Acyclic activated alkenes/ alkynes 5450 2.1.2. Cyclic activated alkenes 5451 2.2. Electrophiles 5451 2.3. Catalysts 5452 3. Essential Components: Recent Developments 5452 3.1. Activated Alkenes/Alkynes 5452 3.2. Electrophiles 5460 3.3. Catalysts 5477 4. Asymmetric Baylis-Hillman Reaction: Earlier Developments 5495

Recent contributions from the Baylis-Hillman reaction to organic chemistry.

Pyrrolidines and piperidines are important building blocks in organic synthesis. Numerous methods exist for constructing substituted pyrrolidines and piperidines. However, efficient syntheses of pyrrolidines and piperidines bearing chiral tertiary alcohols are limited. Here we report an efficient enantioselective nickel-catalyzed intramolecular reductive cyclization of N-alkynones. A P-chiral bisphosphorus ligand DI-BIDIME is designed and applied in the synthesis of tertiary allylic siloxanes bearing pyrrolidine and piperidine rings in high yields and excellent enantioselectivities, with triethylsilane as reducing reagent. The highest turn over number achieved is 1000 (0.1 mol% catalyst loading) with > 99:1 er. This reaction provides a practical way to synthesize pyrrolidine and piperidine derivatives with chiral tertiary alcohols from easily accessible starting materials under mild conditions. The products can be scaled up and transformed to various useful chiral intermediates. The P-chiral bisphosphorus ligand developed in this study represents one of the few ligands for highly enantioselective cyclization of alkynones. Transition metal-catalyzed cyclization of alkynes and carbonyls offers a useful route to cyclic allylic alcohols, but typically uses precious metal catalysts. Here, enantioselective nickel-catalyzed reductive cyclization of N-alkynones gives tertiary allylic alcohols in up to 99:1 er with catalyst loadings of 0.1 mol%

/pdf/pyrrolidines-and-piperidines-bearing-chiral-tertiary-2z5mytem5q.pdf

Pyrrolidines and piperidines bearing chiral tertiary alcohols by nickel-catalyzed enantioselective reductive cyclization of N -alkynones

Described herein are methods of syntheses of phosphorous atom-modified nucleic acids comprising chiral X-phosphonate moieties. The methods described herein provide backbone-modified nucleic acids in high diasteteomeric purity via an asymmetric reaction of an achiral molecule comprising a chemically stable H-phophonate moiety with a nucleoside/nucleotide.

Method for the synthesis of phosphorus atom modified nucleic acids

To provide a chiral reagent or a salt thereof. The chiral reagent has following chemical formula (I). In the formula (I), G1 and G2 are independently a hydrogen atom, a nitro group (-NO2), a halogen atom, a cyano group (-CN), a group of formula (II) or (III), or both G1 and G2 taken together to form a group of formula (IV).

Asymmetric auxiliary group

Described herein are methods for the synthesis of derivatives of thiosulfonate reagents. Said reagents have utility for the synthesis of phosphorothiotriesters from H- phosphonates in a stereospecific fashion.

Methods for the synthesis of functionalized nucleic acids

A series of 1,3,3,4-tetrasubstituted pyrrolidine containing CCR5 receptor antagonists were designed, which were elaborated either by condensation of a lithium salt of 3-(N,N-dibenzyl)aminopropionic acid methyl ester with ethyl benzoformate or by Baylis-Hillman reaction of ethyl acrylate with ethyl benzoformate and subsequent 1,4-addition of benzylamine, in the key steps. These compounds bearing 4-(N,N-disubstituted)amino piperidine units showed low nanomolar potency against the CCR5 receptor, whereas molecules with a 4-phenylpiperidine moiety displayed poor activity. Asymmetric synthesis of the most potent compound 23 a gave rise to the (3R,4S)-enantiomer 30 and the (3S,4R)-enantiomer 31, which showed IC(50) values of 2.9 and 385.9 nM, respectively. These results indicated that (3R,4S)-configuration in the series of compounds is favored for their interaction with the CCR5 receptor. The possible binding mode of these antagonists with the CCR5 receptor was discussed using a computer-modeling method. Compound 30 displayed excellent replication inhibition of seven genetically diverse R5 HIV-1 strains in the PBMC model, in a concentration-dependent manner with EC(50) values ranging from 0.3 nM to 30 nM. This molecule showed oral bioavailabilities of 41.2 % and 21.6 % in rats and dogs, respectively. Thus, compound 30 is a promising candidate for the treatment of HIV-1 infection.

Synthesis and Biological Evaluation of 1,3,3,4‐Tetrasubstituted Pyrrolidine CCR5 Receptor Antagonists. Discovery of a Potent and Orally Bioavailable Anti‐HIV Agent

The present invention discloses the compounds of formula ( I ) or a pharmaceutically acceptable derivative, salt or prodrug thereof, which can inhibit HIV replication.

Pyrollidine-based compounds

The invention belongs to the technical field of biology and discloses a particular genetic construct. The construct is compatible with TPA response elements, cytomegalovirus promoters, and elements of report gene and resistance gene, and the elements can be favorably matched and can report the condition of a protein kinase C signal channel in a cell in high sensitivity after being transfected into a mammalian cell. The invention also discloses a vector containing the construct, and a cell containing the vector. The cell can be taken as a model used for screening adjustment medicament of the protein kinase C signal channel. The report gene cell model can be used for screening the medicament related to the protein kinase C signal channel. The report gene cell model has the characteristics of clear mechanism, simple operation and high-pass quantization and has positive significance for screening the medicament related to the protein kinase C signal channel.

Report gene cell model for screening medicament and construction method thereof

The present invention discloses the compounds of formula I or their pharmaceutically acceptable salts, which are useful as CCR5 antagonists. The preparation and use of the compounds of formula I, pharmaceutical composition containing the same are also disclosed. Furthermore, the present invention discloses an intermediate for the preparation of the compounds of formula I.

Compounds as CCR5 antagonists

Compounds as cor5 antagonists

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