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The myxobacterial natural product myxocoumarin A from Stigmatella aurantiaca MYX-030 has remarkable antifungal activity against agriculturally relevant pathogens. To broaden the initial evaluation of its biological potential, we herein completed the first total synthesis of myxocoumarin A. This synthetic access facilitated stereochemical investigations on the natural product structure, revealing its (R)-configuration. Biological activity profiling showed a lack of activity against Candida spp. and Gram-negative bacteria but revealed strong antibiotic activities against Bacillus subtilis and Staphylococcus aureus, including MRSA.

Nickel(II)-aryl complexes [(L-2)Ni(Ar)Br] bearing either chiral phosphine ligands (L-2=RR- orSS-DIPAMP, Ar =ortho-anisyl), or a chiral aryl-group have been prepared, and their structural optical an chiroptical properties have been characterized. Enantiomeric pairs of both catalysts have been used for the asymmetric polymerization of different isocyanides (M1,M2,M3), to give well defined polyisocyanides (P1,P2,P3). Their polymerization behavior has been studied, which confirmed chain-growth polymerization in all cases. The asymmetric induction has been verified by circular dichroism spectroscopy on enantiomeric pairs of all three polymers.

Nickel(II)-aryl complexes [(L-2)Ni(Ar)Br] bearing either chiral phosphine ligands (L-2=RR- orSS-DIPAMP, Ar =ortho-anisyl), or a chiral aryl-group have been prepared, and their structural optical an chiroptical properties have been characterized. Enantiomeric pairs of both catalysts have been used for the asymmetric polymerization of different isocyanides (M1,M2,M3), to give well defined polyisocyanides (P1,P2,P3). Their polymerization behavior has been studied, which confirmed chain-growth polymerization in all cases. The asymmetric induction has been verified by circular dichroism spectroscopy on enantiomeric pairs of all three polymers.

Nickel(II)-aryl complexes [(L-2)Ni(Ar)Br] bearing either chiral phosphine ligands (L-2=RR- orSS-DIPAMP, Ar =ortho-anisyl), or a chiral aryl-group have been prepared, and their structural optical an chiroptical properties have been characterized. Enantiomeric pairs of both catalysts have been used for the asymmetric polymerization of different isocyanides (M1,M2,M3), to give well defined polyisocyanides (P1,P2,P3). Their polymerization behavior has been studied, which confirmed chain-growth polymerization in all cases. The asymmetric induction has been verified by circular dichroism spectroscopy on enantiomeric pairs of all three polymers.

Nickel(II)-aryl complexes [(L-2)Ni(Ar)Br] bearing either chiral phosphine ligands (L-2=RR- orSS-DIPAMP, Ar =ortho-anisyl), or a chiral aryl-group have been prepared, and their structural optical an chiroptical properties have been characterized. Enantiomeric pairs of both catalysts have been used for the asymmetric polymerization of different isocyanides (M1,M2,M3), to give well defined polyisocyanides (P1,P2,P3). Their polymerization behavior has been studied, which confirmed chain-growth polymerization in all cases. The asymmetric induction has been verified by circular dichroism spectroscopy on enantiomeric pairs of all three polymers.

Nickel(II)-aryl complexes [(L-2)Ni(Ar)Br] bearing either chiral phosphine ligands (L-2=RR- orSS-DIPAMP, Ar =ortho-anisyl), or a chiral aryl-group have been prepared, and their structural optical an chiroptical properties have been characterized. Enantiomeric pairs of both catalysts have been used for the asymmetric polymerization of different isocyanides (M1,M2,M3), to give well defined polyisocyanides (P1,P2,P3). Their polymerization behavior has been studied, which confirmed chain-growth polymerization in all cases. The asymmetric induction has been verified by circular dichroism spectroscopy on enantiomeric pairs of all three polymers.

Nickel(II)-aryl complexes [(L-2)Ni(Ar)Br] bearing either chiral phosphine ligands (L-2=RR- orSS-DIPAMP, Ar =ortho-anisyl), or a chiral aryl-group have been prepared, and their structural optical an chiroptical properties have been characterized. Enantiomeric pairs of both catalysts have been used for the asymmetric polymerization of different isocyanides (M1,M2,M3), to give well defined polyisocyanides (P1,P2,P3). Their polymerization behavior has been studied, which confirmed chain-growth polymerization in all cases. The asymmetric induction has been verified by circular dichroism spectroscopy on enantiomeric pairs of all three polymers.

Chemical investigation of the marine sponge Ircinia oros yielded four linear furanosesterterpenoids, including the known metabolites ircinin-1 (1) and ircinin-2 (2) and two new compounds, ircinialactam E (3) and ircinialactam F (4). Their chemical structures were elucidated by using a combination of [α]D, NMR, HRMS, and FT-IR spectroscopy. The absolute configuration of C-18 in compounds 1–3 was identified as R by electronic circular dichroism (ECD) spectroscopy coupled with time-dependent density functional theory calculations. Compounds 1–4 showed moderate leishmanicidal, trypanocidal, and antiplasmodial activities (IC50 values 28–130 μM). This is the second report of rare glycinyl lactam derivatives 3 and 4 from the genus Ircinia.

Correct assignment of the stereogenic centers of highly flexible linear diterpenes (LDs) is challenging. Herein we report the first application of VCD spectroscopy for the absolute configuration determination of LDs of algal origin and provide experimental and computational procedures, such as a fragmentation approach, which will facilitate the use of VCD spectroscopy for configuration assignments of LDs.

Correct assignment of the stereogenic centers of highly flexible linear diterpenes (LDs) is challenging. Herein we report the first application of VCD spectroscopy for the absolute configuration determination of LDs of algal origin and provide experimental and computational procedures, such as a fragmentation approach, which will facilitate the use of VCD spectroscopy for configuration assignments of LDs.

Vibrational circular dichroism (VCD) spectroscopy is the differential absorption of left- and right-circular polarized light of a chiral molecule during a vibrational transition. In the present work, VCD spectroscopy has been applied to study the molecular conformations and intermolecular interactions of chiral molecules and polymers. In particular, several compounds featuring the alpha-methylbenzyl motif have been studied in order to derive similarities in their spectra. Furthermore, the diastereomeric interaction between chiral ions on the one hand and metal complexes with chiral amines on the other hand have been studied. The helical structures of chiral polymers were studied in the third part of the thesis.

Vibrational circular dichroism (VCD) spectroscopy is the differential absorption of left- and right-circular polarized light of a chiral molecule during a vibrational transition. In the present work, VCD spectroscopy has been applied to study the molecular conformations and intermolecular interactions of chiral molecules and polymers. In particular, several compounds featuring the alpha-methylbenzyl motif have been studied in order to derive similarities in their spectra. Furthermore, the diastereomeric interaction between chiral ions on the one hand and metal complexes with chiral amines on the other hand have been studied. The helical structures of chiral polymers were studied in the third part of the thesis.

Vibrational circular dichroism (VCD) spectroscopy is the differential absorption of left- and right-circular polarized light of a chiral molecule during a vibrational transition. In the present work, VCD spectroscopy has been applied to study the molecular conformations and intermolecular interactions of chiral molecules and polymers. In particular, several compounds featuring the alpha-methylbenzyl motif have been studied in order to derive similarities in their spectra. Furthermore, the diastereomeric interaction between chiral ions on the one hand and metal complexes with chiral amines on the other hand have been studied. The helical structures of chiral polymers were studied in the third part of the thesis.