Rosellin A and B, two red diketopiperazine alkaloids with unprecedented structures, have been isolated from the fruiting bodies of the mushroom Mycena rosella. The structures of the rosellins were mainly deduced from their 2D NMR and HRMS (ESI) spectra. Their absolute configuration was determined by comparison of the CD spectra of the rosellins with the corresponding CD spectra obtained by quantum chemical calculations. Root exposure to rosellin A led to bleaching of the leaves of Lepidium sativum plants.

The first total synthesis of cordyheptapeptide A is described. The synthesis is accomplished by a convergent approach featuring a combination of peptide coupling and the Ugi reaction for the preparation of the main building blocks and the acyclic precursor. The assembly of an N-methylated fragment by the Ugi reaction comprised the utilization of a convertible isonitrile followed by activation of the C-terminal amide. Two different macrocyclization sites were evaluated, proving greater efficacy the macrolactamization at the site Ile-Tyr, likely due of a more suitable conformational bias of the acyclic precursor having an internal β-turn centered at the N-Me-d-Phe-Pro moiety.

Four new hygrophorones (1–4) together with the known hygrophorone B12 (5) have been isolated from fruiting bodies of the basidiomycete Hygrophorus abieticola Krieglst. ex Gröger & Bresinsky. Their structures were assigned on the basis of extensive one and two dimensional NMR spectroscopic analyses as well as ESI-HRMS measurements. Among these compounds, two previously undescribed hygrophorone types, named hygrophorone H12 (3) and 2,3-dihydrohygrophorone H12 (4), were identified. The absolute configuration of hygrophorone E12 (2) is suggested based on quantum chemical CD calculations, while a semisynthetic approach in conjunction with computational studies and analysis of NOE interactions allowed the stereochemical assignment of compounds 3 and 4. Additionally, semisynthetic derivatives of hygrophorone B12 (5) were generated by acetylation of the hydroxyl groups. The biological activity of the natural and semisynthetic hygrophorones was evaluated against phytopathogenic organisms, revealing that the α,β-unsaturated carbonyl functionality is likely to be an essential structural feature. Hygrophorone B12 (5) was identified as the most active compound, acting against both ascomycetous fungi and oomycetes.

The first total synthesis of cordyheptapeptide A is described. The synthesis is accomplished by a convergent approach featuring a combination of peptide coupling and the Ugi reaction for the preparation of the main building blocks and the acyclic precursor. The assembly of an N-methylated fragment by the Ugi reaction comprised the utilization of a convertible isonitrile followed by activation of the C-terminal amide. Two different macrocyclization sites were evaluated, proving greater efficacy the macrolactamization at the site Ile-Tyr, likely due of a more suitable conformational bias of the acyclic precursor having an internal β-turn centered at the N-Me-d-Phe-Pro moiety.

Four new hygrophorones (1–4) together with the known hygrophorone B12 (5) have been isolated from fruiting bodies of the basidiomycete Hygrophorus abieticola Krieglst. ex Gröger & Bresinsky. Their structures were assigned on the basis of extensive one and two dimensional NMR spectroscopic analyses as well as ESI-HRMS measurements. Among these compounds, two previously undescribed hygrophorone types, named hygrophorone H12 (3) and 2,3-dihydrohygrophorone H12 (4), were identified. The absolute configuration of hygrophorone E12 (2) is suggested based on quantum chemical CD calculations, while a semisynthetic approach in conjunction with computational studies and analysis of NOE interactions allowed the stereochemical assignment of compounds 3 and 4. Additionally, semisynthetic derivatives of hygrophorone B12 (5) were generated by acetylation of the hydroxyl groups. The biological activity of the natural and semisynthetic hygrophorones was evaluated against phytopathogenic organisms, revealing that the α,β-unsaturated carbonyl functionality is likely to be an essential structural feature. Hygrophorone B12 (5) was identified as the most active compound, acting against both ascomycetous fungi and oomycetes.

Organocatalytic nucleophilic addition of 2-hydroxylnaphthaquinone to imines is reported. This new route can be used to produce enantioenriched Mannich bases with excellent yields and moderate enantioselectivities.

Organocatalytic nucleophilic addition of 2-hydroxylnaphthaquinone to imines is reported. This new route can be used to produce enantioenriched Mannich bases with excellent yields and moderate enantioselectivities.

Organocatalytic nucleophilic addition of 2-hydroxylnaphthaquinone to imines is reported. This new route can be used to produce enantioenriched Mannich bases with excellent yields and moderate enantioselectivities.

Takai–Utimoto reactions with secondary and tertiary aliphatic halides usually failed according to previous reports. Now, significant improvements could be achieved, and especially secondary aliphatic halides can be coupled to aromatic aldehydes in yields of up to >95%. A variety of processes are competing with the desired one, and thus conditions must be adapted to the nature of the aldehyde as well as the aliphatic halide used, as the outcome of these reactions is strongly affected by the putative radical intermediates.

Takai–Utimoto reactions with secondary and tertiary aliphatic halides usually failed according to previous reports. Now, significant improvements could be achieved, and especially secondary aliphatic halides can be coupled to aromatic aldehydes in yields of up to >95%. A variety of processes are competing with the desired one, and thus conditions must be adapted to the nature of the aldehyde as well as the aliphatic halide used, as the outcome of these reactions is strongly affected by the putative radical intermediates.