Structure-activity relationships in chemically modified coumermycin

Structure-activity relationships in chemically modified coumermycin.

ABSTRACT Coumermycin A1 was early recognized as a potentially useful antibiotic because of its very good spectrum of activity against gram-positive organisms (particularly against staphylococci), in addition to appreciable activity against a variety of gram-negative bacteria. However, in spite of its excellent in vitro activity, the insoluble character of coumermycin A1 made parenteral administ...

Structure and biological activity of chemically modified nisin A species.

Nisin, a 34-residue peptide bacteriocin, contains the less common amino acids lanthionine, beta-methyl-lanthionine, dehydroalanine (Dha), and dehydrobutyrine (Dhb). Several chemically modified nisin A species were purified by reverse-phase HPLC and characterized by two-dimensional NMR and electrospray mass spectrometry. Five constituents, [2-hydroxy-Ala5]nisin, [Ile4-amide,pyruvyl-Leu6]des-Dha5...

Synthesis and initial structure--activity relationships of modified salicylihalamides.

[reaction:see text] The first stereoselective total synthesis of the potent antitumor compound (-)-salicylihalamide A is presented. The practicality of our approach provides for high material throughput and is highlighted by the rapid construction of a variety of modified congeners. Initial structure-activity relationships are derived from growth inhibition experiments with a human melanoma can...

Structure-radical scavenging activity relationships of hydroxytoluene derivatives

Research works proposed that radical scavenging activity of flavonoids is due to ring B, andthe remaining part of the molecule can be disregarded. Thus the objective of this work is toobserve whether hydroxytoluenes account the radical scavenging activity of flavonoid and toestablish structural requirements for their activity (as they showed appreciable activity) andelucidate a comprehensive me...

Structure-activity relationships in cannabinoids.