N-Substituted 3-Acetyltetramic Acid Derivatives as Antibacterial Agents
作者:Raghunandan Yendapally、Julian G. Hurdle、Elizabeth I. Carson、Robin B. Lee、Richard E. Lee
DOI:10.1021/jm701356q
日期:2008.3.13
expand the structure-activity relationship of tetramic acid molecules with structural similarity to the antibiotic reutericyclin, 22 compounds were synthesized and tested against a panel of clinically relevant bacteria. Key structural changes on the tetramic acid core affected antibacterial activity. Various compounds in the N-alkyl 3-acetyltetramic acid series exhibited good activity against Gram-positive
Facile Synthesis of β-Amino
Disulfides, Cystines, and Their Direct Incorporation into
Peptides
作者:Srinivasan Chandrasekaran、Nasir Baig R. B.、Catherine Kanimozhi、V. Sai Sudhir
DOI:10.1055/s-0028-1088133
日期:——
the synthesis of beta-amino disulfides by regioselectiveringopening of sulfamidates with benzyltriethylammonium tetrathiomolybdate [BnNEt3](2)MoS4. Stability and reactivity of different protecting groups under the reaction conditions have been discussed. This methodology has also been extended to serine and threonine derived sulfamidates to furnish cystine and 3,3'-dimethyl cystine derivatives.
A facile stereospecific synthesis of α-hydrazino esters
作者:Umut Oguz、Garett G. Guilbeau、Mark L. McLaughlin
DOI:10.1016/s0040-4039(02)00352-0
日期:2002.4
A convenient route to make α-hydrazino esters from their corresponding α-amino esters is reported. A key step is selective nitrosamine reduction using activated Zn, conc. HCl, and methanol at low temperatures giving nearly quantitative yields of the pure α-hydrazino esters
Tetramic acid analogues of Formula I and Formula II have antibacterial activity, primarily against gram-positive bacteria, and are iron chelators.
Formula I和Formula II的四羧酸类似物具有抗菌活性,主要针对革兰氏阳性细菌,并且是铁螯合剂。
Asymmetric tandem Mannich-Michael reactions of amino acid ester imines with Danishefsky's diene
作者:H. Waldmann、M. Braun
DOI:10.1021/jo00042a027
日期:1992.7
Imines 1 derived from aromatic, aliphatic, and functionalized aldehydes and various amino acid esters react with Danishefsky's diene under Lewis acid catalysis via a tandem Mannich-Michael mechanism to give cyclic 6-substituted 2,3-didehydro-4-piperidinones in good to high yields and with diastereomeric ratios reaching from 92:8 up to 97:3. The chiral auxiliary is removed by conversion of the alpha-C atom of the amino acid into an acetalic center, employing a Curtius reaction as the key step. For the elucidation of the absolute configuration, the alkaloids (S)-coniine and (R)-delta-coniceine are synthesized from the enaminones 5i and 5r.