δ,ε-Unsaturated α,β-Diamino Acids as Building Blocks for the Asymmetric Synthesis of Diverse α,β-Diamino Acids

Catalytic Asymmetric Access to Noncanonical Chiral α-Amino Acids from Cyclic Iminoglyoxylates and Enamides

Here we describe an enantioselective Mannich reaction of cyclic iminoglyoxylates with enamides by virtue of chiral phosphoric acid catalysis in a one-pot manner. The wide substrate scope, mild reaction conditions, and constantly excellent enantioselectivities (>95% ee in most cases) render this protocol highly practical for the rapid construction of valuable noncanonical chiral α-amino-acid building blocks.

Reactions of Allylmagnesium Reagents with Carbonyl Compounds and Compounds with C═N Double Bonds: Their Diastereoselectivities Generally Cannot Be Analyzed Using the Felkin-Anh and Chelation-Control Models

This review describes the additions of allylmagnesium reagents to carbonyl compounds and to imines, focusing on the differences in reactivity between allylmagnesium halides and other Grignard reagents. In many cases, allylmagnesium reagents either react with low stereoselectivity when other Grignard reagents react with high selectivity, or allylmagnesium reagents react with the opposite stereoselectivity. This review collects hundreds of examples, discusses the origins of stereoselectivities or the lack of stereoselectivity, and evaluates why selectivity may not occur and when it will likely occur.

Stereodivergent routes in organic synthesis: carbohydrates, amino acids, alkaloids and terpenes

The natural occurrence of enantiomers and diastereomers is often encountered.

Synthesis of 2-aminosuberic acid derivatives as components of some histone deacetylase inhibiting cyclic tetrapeptides

A new synthesis of the important amino acid 2-aminosuberic acid from aspartic acid is reported. The methodology involves the alternate preparation of (S)-2-aminohept-6-enoate ester as a building block and its diversification through a cross-metathesis reaction to prepare the title compounds. The utility of the protocol is demonstrated through the preparation of three suberic acid derivatives of relevance to the design and the synthesis of peptides of biological relevance.

Synthetic Approaches toward Monocyclic 3-Amino-β-lactams

Due to the emerging resistance against classical β-lactam-based antibiotics, a growing number of bacterial infections has become harder to treat. This alarming tendency necessitates continued research on novel antibacterial agents. Many classes of β-lactam antibiotics are characterized by the presence of the 3-aminoazetidin-2-one core, which resembles the natural substrate of the target penicillin-binding proteins. In that respect, this Review summarizes the different synthetic pathways toward this key structure for the development of new antibacterial agents. The most extensively applied methods for 3-amino-β-lactam ring formation are discussed, in addition to a few less common strategies. Moreover, approaches to introduce the 3-amino substituent after ring formation are also covered.