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An approach to the synthesis of sulfonamides from sulfamoyl inner salts and organometallic species is presented. A range of sulfamoyl carbamates, amines, and metals are explored. Primary, secondary, and tertiary alkyl-, aryl-, and heteroaryllitihium and magnesium nucleophiles were successful. This approach yields bench-stable intermediates and avoids many of the functional group incompatibilities, regioselectivity issues, and high-energy reagents generally associated with the synthesis of sulfonamides. Additionally, the products may be purified by basic extraction or salt formation, avoiding chromatography. [ABSTRACT FROM AUTHOR]

The assembling behavior of four thiophene-containingconjugatedpolymers, regioregular poly(3-hexythiophene) (rr-P3HT), poly(3,3-didodecylquaterthiophene)(PQT-12), poly(2,5-bis(3- tetradecylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT-14), and poly(2,5-bis(3-tetradecylthiophen-2-yl)thiophen-2-yl)thiophen-2-ylthiazolo[5,4-d]thiazole)(PTzQT-14), on carbon nanotubes was investigated through microscopicstudies of nanowire formation and theoretical simulation. It is foundthat polymer backbone rigidity and shape influence the attachmentmode on carbon nanotubes. rr-P3HT and PQT-12 have a zigzag backbonestructure that allows a thermodynamically stable coaxial attachmenton CNTs, providing an ordered growth front for the nanowire formation.In contrast, fused rings in PTzQT-14 and PBTTT-14 create a stair-steplike backbone structure that causes a kinetically controlled wrappingconformation on CNTs, generating a twisted growth front that hindersthe nanowire formation. In addition, the rigidity of polymer backboneinfluences the wrapping mode. Polymers with more flexible backbones(i.e., PBTTT-14) would take a dense irregular wrapping mode on CNTs.The CNT diameter plays an important role in the nanowire formationwhen CPs attach to the CNT in the wrapping mode. Larger nanotubeswith smaller surface curvature provides a less twisted polymer growthfront, allowing the formation of CPNWs. [ABSTRACT FROM AUTHOR]

Potato peel, a waste product of the potato processing industry, is high in bioactive compounds. We investigated the in vitro antitrichomonad activity of potato peel powders prepared from commercial Russet, red, purple, and fingerling varieties as well as several known potato components, alkaloids and phenolic compounds, against three pathogenic strains of trichomonads. Trichomonas vaginalis is a sexually transmitted protozoan parasite that causes the human disease trichomoniasis. Two distinct strains of the related Tritrichomonas fetus infect cattle and cats. The glycoalkaloids α-chaconine and α-solanine were highly active against all parasite lines, while their common aglycone solanidine was only mildly inhibitory. α-Solanine was several times more active than α-chaconine. The phenolic compounds caffeic and chlorogenic acids and quercetin were mildly active against the parasites. Most of the potato peel samples were at least somewhat active against all three trichomonad species, but their activities were wide-ranging and did not correspond to their glycoalkaloid and phenolic content determined by HPLC. The two Russet samples were the most active against all three parasites. The purple potato peel sample was highly active against bovine and mostly inactive against feline trichomonads. None of the test substances were inhibitory toward several normal microflora species, suggesting the potential use of the peels for targeted therapeutic treatments against trichomonads.

As part of our effort in identifying phosphodiesterase (PDE) 4B-preferring inhibitors for the treatment of central nervous system (CNS) disorders, we sought to identify a positron emission tomography (PET) ligand to enable target occupancy measurement in vivo. Through a systematic and cost-effective PET discovery process, involving expression level (B max ) and biodistribution determination, a PET-specific structure-activity relationship (SAR) effort, and specific binding assessment using a LC-MS/MS "cold tracer" method, we have identified 8 (PF-06445974) as a promising PET lead. Compound 8 has exquisite potency at PDE4B, good selectivity over PDE4D, excellent brain permeability, and a high level of specific binding in the "cold tracer" study. In subsequent non-human primate (NHP) PET imaging studies, [ 18 F]8 showed rapid brain uptake and high target specificity, indicating that [ 18 F]8 is a promising PDE4B-preferring radioligand for clinical PET imaging.

The identification of centrally efficacious β-secretase (BACE1) inhibitors for the treatment of Alzheimer's disease (AD) has historically been thwarted by an inability to maintain alignment of potency, brain availability, and desired absorption, distribution, metabolism, and excretion (ADME) properties. In this paper, we describe a series of truncated, fused thioamidines that are efficiently selective in garnering BACE1 activity without simultaneously inhibiting the closely related cathepsin D or negatively impacting brain penetration and ADME alignment, as exemplified by 36. Upon oral administration, these inhibitors exhibit robust brain availability and are efficacious in lowering central Amyloid β (Aβ) levels in mouse and dog. In addition, chronic treatment in aged PS1/APP mice effects a decrease in the number and size of Aβ-derived plaques. Most importantly, evaluation of 36 in a 2-week exploratory toxicology study revealed no accumulation of autofluorescent material in retinal pigment epithelium or histology findings in the eye, issues observed with earlier BACE1 inhibitors.

A stereoselective synthesis of spiropiperidine compounds, exemplified by compound 1, was developed, which was based upon the late stage N-arylation of a 1,8-diazaspiro[4.5]dec-3-en-2-one pharmacophore. Previously, compound 1 was prepared in low overall yield from piperidinone 2 via the Strecker reaction. A new route was developed, which employed the stereospecific Corey-Link reaction of an enantiomerically pure trichloromethylcarbinol to give a template compound amenable to late stage N-arylation.

Relatively little is known about how liposomal formulations modulate drug delivery to fungal pathogens. We compared patterns of hyphal cell wall binding for empty rhodmine-labeled liposomes and the clinically available amphotericin B-containing liposomal formulation (AmBisome) in Aspergillus fumigatus and Candida albicans. Following 0.5 h of coincubation with A. fumigatus , empty liposomes concentrated primarily in fungal septae along at the surface of the cell wall, suggesting that liposome uptake is concentrated in areas of the cell wall where linear glucan is exposed on the cell surface, which was confirmed by aniline blue staining. Consistent with this hypothesis, pretreatment of liposomes with soluble linear glucan (laminarin) decreased liposome binding in both Aspergillus and Candida fungal hyphae, while growth of Aspergillus hyphae in the presence of an agent that increases fungal cell wall surface exposure of linear β-glucans without cell death (caspofungin) increased liposome uptake throughout the Aspergillus fungal cell wall. Increasing the polyethylene glycol (PEG) concentration in liposomes from 0 to 30% significantly increased fungal uptake of liposomes that was only modestly attenuated when fungal cells were incubated in serum concentrations ranging from 10 to 100%. The presence of β-glucans on the fungal hyphae cell walls of Aspergillus fumigatus is one of the factors responsible for mediating the binding of liposome carriers to the hyphae and could explain possible synergy reported between liposomal amphotericin B and echinocanins.