Publications by authors named "R Kullnig"

Novel antiherpetic 3-quinolinecarboxamides were discovered as part of a drug discovery program at Sterling Winthrop Inc. A major goal of this research was to identify novel non-nucleoside agents possessing activity against acyclovir resistant herpes simplex virus. From screening compound libraries in an HSV-2 plaque reduction assay, 1-ethyl-1,4-dihydro-4-oxo-7-(4-pyridinyl)-3-quinolinecarboxamide (1) emerged as an attractive lead structure.

View Article and Find Full Text PDF

The synthesis and in vitro and in vivo evaluation of 12,13-cycloalkyl-6,11-ethanobenzo[b]-quinolizidines, a new class of noncompetitive N-methyl-D-aspartate (NMDA) antagonists acting at the PCP site on the NMDA receptor complex, is reported. Structure-activity relationship studies led to the identification of 10-hydroxy-(6 alpha,11 alpha,11 alpha beta,12R*,13S*)-1,3,4,6,11,11a,13,14,15,16-decahydro-12H- 6,11[1',2']-endo-cyclopenta-2H-pyrido[1,2-b]isoquinoline hydrobromide (5h) and 9-hydroxy-(6 alpha,11 alpha,11a beta,12R*,13S*)- 1,3,4,6,11,11a,13,14,15,16-decahydro-12H-6,11-[1',2']-endo-cycl ope nta-2H- pyrido[1,2-b]isoquinoline hydrobromide (5i), the most potent members of this series with Ki values of 2.3 +/- 0.

View Article and Find Full Text PDF

Three new compounds, named fiscalins A, B, and C, were found in culture broth produced by a Neosartorya fischeri. These compounds inhibit the binding of radiolabeled substance P ligand to the human neurokinin (NK-1) receptor, with Ki values of 57, 174, and 68 microM, respectively. Detailed spectroscopic and amino acid analyses led to the elucidation of structures for the three fiscalins.

View Article and Find Full Text PDF

Substance P (SP) is an undecapeptide belonging to a family of chemically related neurotransmitters and neuromodulators known as neurokinins. In our search for SP antagonists, we screened microbial broth extracts for the ability to inhibit radiolabeled SP binding to membranes prepared from rat forebrain. Anthrotainin was isolated from a fungal culture and determined to be a novel tetracyclic compound, with an IC50 of 3 microM against [125I]SP.

View Article and Find Full Text PDF

Complementarity of electrostatic potential surface maps was utilized in defining bioisosteric steroidal androgen receptor antagonists. Semiempirical and ab initio level calculations performed on a series of methanesulfonyl heterocycles indicated the requirement for a partial negative charge at the heteroatom attached to C-3 of the steroid nucleus to attain androgen receptor affinity. Synthesis and testing of six heterocycle A-ring-fused dihydroethisterone derivatives support this hypothesis, and we have identified two new androgen receptor antagonists of this class.

View Article and Find Full Text PDF