The design, synthesis, and development of a new class of modular, strongly basic, and tunable bifunctional Brønsted base/H-bond-donor organocatalysts are reported. These catalysts incorporate a triaryliminophosphorane as the Brønsted basic moiety and are readily synthesized via a last step Staudinger reaction of a chiral organoazide and a triarylphosphine. Their application to the first general...

We present three versatile solid-supported scaffold building blocks based on the (deoxy)cholic acid framework and decorated with handles for further derivatization by modern ligation techniques such as click chemistry, Staudinger ligation or native chemical ligation. Straightforward procedures are presented for the synthesis and analysis of the steroid constructs. These building blocks offer a ...

Novel, efficient and mild preparation of 7- and 8-membered cyclic di- and 10-membered cyclic tripeptides containing α-, β- or γ-amino acid residues is effected by a Staudinger-mediated ring closure. Medium-sized cyclic di- and tripeptides--recognized as difficult targets--were obtained in moderate to good yields according to a straightforward sequence. Empirical force-field calculations were un...

Proteins have become accessible targets for chemical synthesis. The basic strategy is to use native chemical ligation, Staudinger ligation, or other orthogonal chemical reactions to couple synthetic peptides. The ligation reactions are compatible with a variety of solvents and proceed in solution or on a solid support. Chemical synthesis enables a level of control on protein composition that gr...

Krystyna Lesiak and Wojciech J. Stec Polish Academy of Sciences, Centre of Molecular and Macromolecular Studies, 90-362 Lodz, Boczna 5, Poland Z. Naturforsch. 33b, 782-785 (1978); received March 28, 1978 1,3,2-Oxazaphospholidines, (—)Ephedrine, Thioanilides, Thioesters, Stereochemistry Both isomers of 2-anilido-3,4-dimethyl-5-phenyl-l,3,2-oxazaphospholidine-2-thiones (2 a and 2 b) derived from ...

The Balkan Lepidoptera fauna is still not comprehensively known. We present here some new records for three countries. Polymixis xanthomista (Hübner, [1819]) confirmed the Peninsula from Albania, Eriogaster inspersa Staudinger, 1879 reported Republic of North Macedonia (second locality in Europe), and Mythimna languida (Walker, 1858) Bulgaria. Some other species ( Ctenoplusia accentifera (Lefèb...

We report new findings of rare and little studied Macrolepidoptera species the Ural Mountains. The localities are revealed: Euchloe ausonia (Hübner, [1804[), Boloria aquilonaris (Stichel, 1908), Oeneis jutta [1806]), Xestia lorezi (Staudinger, 1891), X. sincera (Herrich-Schäffer, 1851), Coenophyla subrosea (Stephens, 1829). For first time, following reported from Urals: Apamea schildei 1901), C...

ISSN 0418{9833 MZ-TH/00{09 hep{ph/0003148 Mar h 2000 Gluon Fragmentation to Gluonium H. Spiesberger1 and P. M. Zerwas2 1 Institut f ur Physik, Johannes-Gutenberg-Universitat, Staudinger Weg 7, D-55099 Mainz, Germany 2 Deuts hes Elektronen-Syn hrotron DESY, D-22603 Hamburg, Germany Abstra t The fragmentation of gluons to gluonium states is analyzed qualitatively in the nonperturbative region. ...