Quaternary ammonium compounds, effective as sanitizing agents for food plant equipment under certain conditions, are not well suited as sanitizers for water of high mineral content. Mueller and Seeley (1951) have demonstrated under controlled conditions that various metallic cations can decrease the germicidal action of a quaternary in solution. Knowledge of how such interference takes place co...

The progress of antimicrobial therapy contributes to the development of strains of fungi resistant to antimicrobial drugs. Since cationic surfactants have been described as good antifungals, we present a SAR study of a novel homologous series of 140 bis-quaternary imidazolium chlorides and analyze them with respect to their biological activity against Candida albicans as one of the major opport...

In the title compound, C(19)H(26)O(2), the A ring adopts a chair conformation, whereas the B and C rings both adopt distorted half-chair conformations with the quaternary C atom common to both rings lying 0.577 (3) and 0.648 (3) Å out of the approximate plane defined by the remaining five C atoms (r.m.s. deviations = 0.1386 and 0.1156 Å) for the B and C rings, respectively. Mol-ecules are assem...

We use Quaternary stratigraphy to reconstruct landscape evolution and measure tectonic deformation of the Olympic Mountains section of the Pacifi c Northwest Coast Range. An important motivation for understanding orogenesis here, and throughout the Coast Range, is the concern about the relationship of active deformation to seismic hazards associated with the Cascadia subduction zone. There is a...

Quaternary nitrogen compounds are being widely used as sanitizers and toimpart bacteriostatic properties to fabrics. When properly applied, the residual quaternary may assist materially in clinical problems associated with the activities of microorganisms in infants' garments, bedding, and similar articles. Directions commonly furnished for the use of these agents specify a unit weight of produ...

Quaternary nitrogen compounds are being widely used as sanitizers and toimpart bacteriostatic properties to fabrics. When properly applied, the residual quaternary may assist materially in clinical problems associated with the activities of microorganisms in infants' garments, bedding, and similar articles. Directions commonly furnished for the use of these agents specify a unit weight of produ...

Allosteric proteins bind an effector molecule at one site resulting in a functional change at a second site. We hypothesize that allosteric communication in proteins relies upon networks of quaternary (collective, rigid-body) and tertiary (residue-residue contact) motions. We argue that cyclic topology of these networks is necessary for allosteric communication. An automated algorithm identifie...

Allosteric proteins, such as hemoglobin, are assemblies of functional units, which undergo quaternary structural transitions in response to concentration changes of a specific ligand. Functional properties of hemoglobin ligation intermediates indicate that the tertiary structural changes induced by the ligand do not promote an equilibrium of quaternary structures.

A catalytic, enantioselective decarboxylative allylic alkylation of 4-thiopyranones is reported. The α-quaternary 4-thiopyranones produced are challenging to access by standard enolate alkylation owing to facile ring-opening β-sulfur elimination. In addition, reduction of the carbon-sulfur bonds provides access to elusive acyclic α-quaternary ketones. The alkylated products are obtained in up t...