Ph3PAuOTf is identified as a powerful catalyst for the addition of difluoroenol silyl ethers to N-Boc isatin ketimines and other two kinds of active cyclic ketimines. This represents the first Au(i)-catalyzed Mukaiyama-Mannich reaction, and the corresponding non-fluorinated enol silyl ether proves to be even much more reactive under the same conditions. This method paves the way to the total sy...

An efficient synthesis of highly functionalized chiral β-amino ester derivatives containing benzothiophene and benzothiazole moieties is developed by a Mannich-type reaction using a cinchona alkaloid-derived thiourea catalyst. The desired products were obtained in good yields and high enantioselectivities (~86% yield, >99% ee) using to the optimized reaction conditions. The synthesized compound...

The title compound, C(18)H(20)N(2)O(2), was prepared by Mannich-type reaction of phenol, ethane-1,2-diamine and formaldehyde. The heterocyclic rings adopt half-chair conformations. The acyclic methyl-ene groups attached to the N atoms are in an axial position. In the crystal, weak C-H⋯O hydrogen bonds link the mol-ecules into dimers. These dimers are further connected via C-H⋯π contacts.

Divergent and concise total syntheses of two lycopodium alkaloids, lyconadins A and C have been developed. The synthesis of lyconadin A, having potent neurotrophic activity, features an efficient one-pot ketal removal and formal aza-[4+2] cyclization to form the cagelike core structure. A tandem ketal removal/Mannich reaction was developed to build the tricyclic structure of lyconadin C. Both l...

A direct asymmetric Mannich reaction using a novel axially chiral amino trifluoromethanesulfonamide (S)-3 has been developed in highly anti-selective and enantioselective manners. Thus, in the presence of a catalytic amount of (S)-3, the reactions between aldehydes and the alpha-imino ester 4 proceed smoothly to give the functional beta-amino aldehydes with significantly higher anti/syn ratio a...

Some new Mannich Bases of 1, 4 Dihydropyridine derivatives were synthesised by reaction of 1, 4 Dihydropyridine derivatives formaldehyde (HCHO) & secondary amines (e.g. morpholine, 1-methyl piperazine) in 1:1 ratio under acidic condition in presence of trace HCl. The compounds synthesised were identified by UV, 1H NMR, and FT-IR spectroscopic techniques. All compounds studied in this work were ...

A methodological study devoted to the Mannich-like multicomponent synthesis of the antiplatelet agent (±)‑clopidogrel (7) and the ethyl ester analogue 6 is described. The process involves the formation of 2-chlorophenyl zinc bromide (2) and its subsequent reaction with an alkyl glyoxylate and 4,5,6,7-tetrahydrothieno[3,2-c]pyridine (3). We demonstrate that the organozinc reagent 2 also constitu...

Stereoselective vinylogous Mannich reaction of 2-trimethylsilyloxyfuran with L-gulose-derived chiral nitrones in the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate was investigated. The selectivity was strongly influenced by the bulkiness of the C-substituent of the nitrone: for example, C-benzyloxymethyl nitrone afforded four stereoisomers, whereas bulky C-[(4S)-2,2...

N-[(Diphenylamino)methyl]acetamide was synthesized using Mannich reaction and its complexes of cerium(IV), thorium(IV) and dioxouranium(VI) were prepared and characterized by elemental analysis and various spectral studies. The bidendate chelation of ligand, bonding through carbonyl oxygen and azomethine nitrogen is suggested. Based on spectral and magnetic studies, hexa coordinate geometry is ...

Amodiaquine (AQ) and tebuquine are 4-aminoquinoline antimalarials with Mannich base side chain and are highly effective against chloroquine (CQ)-resistant strains of Plasmodium falciparum. Clinical use of AQ has been severely restricted due to hepatoxicity and agranulocytosis side effects associated with its long term use. Lysosomal accumulation and bioactivation to generate reactive quinoneimi...