General Synthesis of Conformationally Constrained Noncanonical Amino Acids with C()-Rich Benzene Bioisosteres.

Recent years have seen novel modalities emerge for the treatment of human diseases resulting in an increase in beyond rule of 5 (bRo5) chemical matter. As a result, synthetic innovations aiming to enable rapid access to complex bRo5 molecular entities have become increasingly valuable for medicinal chemists' toolkits. Herein, we report the general synthesis of a new class of noncanonical amino acids (ncAA) with a cyclopropyl backbone to achieve conformational constraint and bearing C()-rich benzene bioisosteres.

Discovery of WAY-260022, a Potent and Selective Inhibitor of the Norepinephrine Transporter.

The potency and selectivity of a series of 1-{(1S)-2-[amino]-1-[3-(trifluoromethoxy)phenyl]ethyl}cyclohexanol analogues are described. These compounds were prepared to improve in vitro metabolic stability and achieve brain penetration. Compound 13 (WAY-260022, NRI-022) was found to be a potent inhibitor of norepinephrine reuptake and demonstrated excellent selectivity over the serotonin and dopamine transporters.

Synthesis and evaluation of azabicyclo[3.2.1]octane derivatives as potent mixed vasopressin antagonists.

A series of biaryl amides containing an azabicyclooctane amine headpiece were synthesized and evaluated as mixed arginine vasopressin (AVP) receptor antagonists. Several analogues, including 8g, 12g, 13d, and 13g, were shown to have excellent V(1a)- and good V(2)-receptor binding affinities. Compound 13d was further profiled for drug-like properties and for an in vitro comparison with conivaptan, the program's mixed V(1a)/V(2)-receptor antagonist standard.

Desmethoxymajusculamide C, a cyanobacterial depsipeptide with potent cytotoxicity in both cyclic and ring-opened forms.

Cytotoxicity-guided fractionation of the organic extract from a Fijian Lyngbya majuscula led to the discovery of desmethoxymajusculamide C (DMMC) as the active metabolite. Spectroscopic analysis including 1D and 2D NMR, MS/MS, and chemical degradation and derivatization protocols were used to assign the planar structure and stereoconfiguration of this new cyclic depsipeptide. DMMC demonstrated potent and selective anti-solid tumor activity with an IC(50) = 20 nM against the HCT-116 human colon carcinoma cell line via disruption of cellular microfilament networks.

Sub-2 microm HPLC coupled with sub-ppm mass accuracy for analysis of pharmaceutical compound libraries.

Recent advances in accurate mass analysis are poised to allow the high-throughput production of accurate mass data on many more compounds than was previously available. It is shown that sub-ppm mass accuracy (producing elemental compositions) can be obtained on a simple TOF mass spectrometer operating in the manufacturer's standard mode. Concomitantly, there have been important technological advances in LC with respect to speed of analysis using sub-2 microm particle columns.

Synthesis and activity of a new class of dual acting norepinephrine and serotonin reuptake inhibitors: 3-(1H-indol-1-yl)-3-arylpropan-1-amines.

Compounds with a combination of norepinephrine and serotonin reuptake inhibition have been approved in the US and Europe for a number of indications, including major depressive disorder and pain disorders such as diabetic neuropathy and fibromyalgia. Efforts to design selective norepinephrine reuptake inhibitors based on SAR from the aryloxypropanamine series of monoamine reuptake inhibitors have led to the identification of a potent new class of dual acting norepinephrine and serotonin reuptake inhibitors, namely the 3-(1H-indol-1-yl)-3-arylpropan-1-amines.

Preparative separation and identification of derivatized beta-methylphenylalanine enantiomers by chiral SFC, HPLC and NMR for development of new peptide ligand mimetics in drug discovery.

A direct preparative purification of all four isomers of the unnatural amino acid beta-methylphenylalanine was achieved using supercritical fluid chromatography (SFC) with stacked-injection. Final purification of the Cbz-methyl ester derived isomers was performed on a Daicel Chiralpak AD-H column (20 mm x 250 mm), using 50:50 methanol/ethanol as the organic modifier and resulted in purification of over 3.4 g of material in 6.

Structure and biosynthesis of the jamaicamides, new mixed polyketide-peptide neurotoxins from the marine cyanobacterium Lyngbya majuscula.

A screening program for bioactive compounds from marine cyanobacteria led to the isolation of jamaicamides A-C. Jamaicamide A is a novel and highly functionalized lipopeptide containing an alkynyl bromide, vinyl chloride, beta-methoxy eneone system, and pyrrolinone ring. The jamaicamides show sodium channelblocking activity and fish toxicity.

Diverse secondary metabolites from a Puerto Rican collection of Lyngbyamajuscula.

Extensive fractionation of the crude organic extract from a Puerto Rican collection of Lyngbya majuscula led to the discovery of three new secondary metabolites: a quinoline alkaloid (1), malyngamide T (2), and a tryptophan derivative (3). In addition, several previously reported compounds, including the potent neurotoxins antillatoxin, antillatoxin B, and kalkitoxin, were identified. The structures of 1, 2, and 3 were deduced by NMR and mass spectral data interpretation and suggest the existence of a convergent biosynthetic pathway for these new and unusual metabolites.

Wewakazole, a novel cyclic dodecapeptide from a Papua New Guinea Lyngbya majuscula.

Phytochemical examination of a Papua New Guinea collection of Lyngbya majuscula resulted in the discovery of wewakazole (1), a novel cyclic dodecapeptide containing an unprecedented six five-membered heterocycles. Multiple NMR experiments and MS/MS data were required to assemble its planar structure because of its extensively signal-overlapped NMR spectra. In particular, a 1D HMBC was utilized to orient a three amino acid fragment that could not be placed by standard spectroscopic methods.

Somocystinamide A, a novel cytotoxic disulfide dimer from a Fijian marine cyanobacterial mixed assemblage.

[reaction: see text] Bioassay-guided investigation of the extract from a Lyngbya majuscula/Schizothrix sp. assemblage of marine cyanobacteria led to the discovery of somocystinamide A (1), an extraordinary disulfide dimer of mixed PKS/NRPS biosynthetic origin. Somocystinamide A (1) was highly acid-sensitive, rapidly and completely converting to a characterizable derivative (2).

Isolation of four new cyclic depsipeptides, antanapeptins A-D, and dolastatin 16 from a Madagascan collection of Lyngbya majuscula.

Examination of a Lyngbya majuscula collection from Antany Mora, Madagascar, led to the isolation of dolastatin 16 (5), a promising antineoplastic metabolite first reported from the marine mollusc Dolabella auricularia. In addition, a new series of depsipeptides, antanapeptins A-D (1-4), were discovered. Their structures were deduced by 2D NMR and mass spectrometry and are analogous to the molluscan kulomo'opunalides and the recently reported cyanobacterial metabolites, georgamide and the yanucamides.