The asymmetric nitro-Mannich reaction of N-phosphoryl imines with α-substituted nitroacetates was performed by using cinchona alkaloid thioureas as organocatalysts in toluene at -20 °C. The present method was highly tolerable to functionalized N-phosphoryl imines and provided a reliable synthetic route to obtain the corresponding β-nitro ethylphosphoramidates with adjacent quaternary and tertia...

A highly efficient asymmetric Mannich-type reaction between α-tetralone-derived β-keto esters/amides and 1,3,5-triaryl-1,3,5-triazinanes was realized in the presence of chiral N,N'-dioxide-Ni(ii) or Mg(ii) complex. A variety of optically active β-amino compounds with all-carbon quaternary stereocenters were obtained in good yields with excellent enantioselectivities. A possible transition state...

An efficient one-pot synthesis of novel β-amino acid derivatives containing a thiadiazole moiety was developed using a chiral squaramide cinchona alkaloid as organocatalyst. The reactions afforded chiral β-amino acid derivatives in moderate yields and with moderate to excellent enantioselectivities. The present study demonstrated for the first time the use of a Mannich reaction catalyzed by a ch...

A series of 2-mercaptobenzimidazole derivatives (MB1–MB5) were synthesized by mannich reaction. The purity of synthesized compounds were determined by melting point and TLC and their structure was established by various analytical techniques such as IR and 1HNMR spectral studies. The newly synthesized compounds were screened for anti-inflammatory activities on carrageenan induced paw oedema in ...

Piperazirum, isolated from Arum palaestinum Boiss, was originally assigned as r-3,c-5-diisobutyl-c-6-isopropylpiperazin-2-one. The reported structure was synthesised diastereoselectively using a key nitro-Mannich reaction to set up the C5/C6 relative stereochemistry. The structure was unambiguously assigned by single crystal X-ray diffraction but the spectroscopic data did not match those repor...

Aim: A variety of Paracetamol derivatives as mannich bases were prepared through mannich reaction by reacting Paracetamol as compound containing active hydrogen, substituted benzaldehyde, morpholine as secondary amine compound and small amount of conc. HCl as catalyst. A simplistic one-pot method under mild conditions has been developed for the synthesis of all the compounds and they were chara...

N-Galactopyranosyland N-glucopyranosyl imines of aliphatic, aromatic and heteroaromatic aldehydes react with 1-methoxy-3-trimethylsilyloxy-1,3-butadiene in a domino Mannich-Michael reaction cascade to give 2-substituted 5,6-dehydro-piperidin-4-ones with high diastereoselectivity. Treatment of these cyclic enaminones with N-bromo-succinimide yields the corresponding 2-substituted 5-bromo-5,6-deh...

Disubstituted [1,3,4]-oxadaiazoles (6a-b), Mannich bases (7a-f) and S-alkylated derivatives (8a-f) have been synthesized from 4-(methylsulfonyl/sulfinyl)phenylaceticacid (3a-b) through a multi-step reaction sequence starting from (4-methylthio)phenylacetonitrile (1). The structures of new compounds were established on the basis of their elemental analysis, IR, H NMR, C NMR and mass spectral dat...

The choice is yours: a highly stereoselective synthesis of α-alkyl-α-hydroxy-β-amino esters is accomplished through a tandem Wittig-rearrangement/Mannich reaction sequence. Transformations of N-benzyl or N-Boc imines proceed with high selectivity for formation of syn-amino alcohol derivatives, whereas N-Boc-2-(phenylsulfonyl)amines generate anti-amino alcohol products. Auxiliary cleavage (trans...

The synthesis of compound (2) was achieved using cyclization method of compound (1) with ethyl chloro acetate and fused sodium acetate. Compound (2) was underwent mannich reaction to give compound (3a-3f). The Chemical structures were elucidated by IR, 1 HNMR, and elemental analysis. The compounds (2) and (3a-3f) have been screened for in vitro antimicrobial action against various strains of ba...