<i>Background:</i> The doctor-patient relationship has been eroded by many factors. Would e-mail enhance communication and address some of the barriers inherent to our medical practices? <i>Methods:</i> Of study population, 4 physicians offered participating patients did not. Both completed questionnaires regarding satisfaction, perceived quality, convenience, promptness communication. <i>Results:</i> Patient satisfaction significantly increased in group compared with control areas...

A biosynthetically inspired synthesis of (+)-liphagal has been achieved from (+)-sclareolide in 13 steps (9% overall yield). The key step is a biomimetic ring expansion highly stabilized benzylic carbocation, which generates the seven-membered and benzofuran natural product single cascade reaction.

Abstract Hyperjapones A–E and hyperjaponols A–C are complex natural products of mixed aromatic polyketide terpene biosynthetic origin that have recently been isolated from Hypericum japonicum . We synthesized hyperjapones using a biomimetic, oxidative hetero‐Diels–Alder reaction to couple together dearomatized acylphloroglucinol cyclic products. Hyperjapone A is proposed be the precursor hyperjaponol C through sequence of: 1) epoxidation; 2) acid‐catalyzed epoxide ring‐opening; 3) concerted,...

Biomimetic syntheses of three polycylic polyprenylated acylphloroglucinol natural products isolated from Hypericum papuanum, ialibinone A, B, and hyperguinone have been accomplished by selective oxidative cyclizations the proposed biosynthetic precursor 5, which was synthesized phloroglucinol in steps.

A full account of our oxidative radical cyclization approach to the synthesis garcibracteatone and doitunggarcinone is presented. This includes first enantioselective garcibracteatone, which allowed absolute configuration natural compound be determined. The also described, confirms reassignment relative this molecule. Novel syntheses monoterpene fragments used construct target molecules are reported.

The polycyclic polyprenylated acylphloroglucinol natural product garcibracteatone has been synthesized in four steps from phloroglucinol, using a strategy based on biosynthetic speculation. key biomimetic transformation is cascade of 7-endo-trig and 5-exo-trig radical cyclizations followed by terminating aromatic substitution reaction.

A structure revision for the recently isolated fungal meroterpenoids, cytosporolides A-C, is suggested based on biosynthetic speculation and reinterpretation of existing spectroscopic data. The supported by a biomimetic synthetic study, featuring [4 + 2] cycloaddition reaction between presumed o-quinone methide intermediate β-caryophyllene.

The biosynthetic route to the napyradiomycin family of bacterial meroterpenoids has been fully described 32 years following their original isolation and 11 after gene cluster discovery. antimicrobial cytotoxic natural products napyradiomycins A1 B1 are produced using three organic substrates (1,3,6,8-tetrahydroxynaphthalene, dimethylallyl pyrophosphate, geranyl pyrophosphate), catalysis via five enzymes: two aromatic prenyltransferases (NapT8 T9); vanadium dependent haloperoxidase (VHPO)...

Abstract The naphterpins and marinones are naphthoquinone meroterpenoids with an unusual aromatic oxidation pattern that is biosynthesized from 1,3,6,8‐tetrahydroxynaphthalene (THN). We propose cryptic halogenation of THN derivatives by vanadium‐dependent chloroperoxidase (VCPO) enzymes key to this biosynthetic pathway, despite the absence chlorine in these natural products. This speculation inspired a total synthesis mimic naphterpin/marinone pathway. In validation biogenetic hypothesis,...

ConspectusNatural products are biosynthesized from a limited pool of starting materials via pathways that obey the same chemical logic as textbook organic reactions. Given structure natural product, it is therefore often possible to predict its likely biosynthesis. Although biosynthesis mainly occurs in highly specific environments enzymes, field biomimetic total synthesis attempts replicate predisposed using reagents.We have followed several guidelines our approach synthesis. The...

The total synthesis of ent-penilactone A and penilactone B has been achieved via biomimetic Michael reactions between tetronic acids o-quinone methides. five-component cascade reaction a acid, formaldehyde, resorcinol derivative that generates four carbon-carbon bonds, one carbon-oxygen bond, two stereocenters in one-pot is also reported.

High-concentration monoclonal antibody (mAb) formulations are frequently constrained by elevated viscosity and colloidal instability, stemming from enhanced intermolecular interactions under crowded conditions. This study delineates the thermodynamic rheological consequences of modulating protein–protein through excipient-mediated temperature-dependent mechanisms. Using an orthogonal analytical framework comprising diffusion interaction parameter ( k D) measurements, high-shear rheometry,...

Inspired: The proposed biosynthetic pathway toward the potent antibiotic meroterpenoid (±)-merochlorin A inspired its concise total synthesis. key steps in synthesis are a one-pot aromatization–alkylation reaction, followed by biomimetic oxidative dearomatization of highly functionalized naphthalene derivative, which forms two rings and four contiguous stereocenters single step.

The structure of siphonodictyal B has been reassigned on the basis total synthesis both possible C-8 epimers. revised was converted into liphagal by acid catalyzed rearrangement a proposed epoxide intermediate. This biomimetic cascade features succession four distinct reactions (epoxidation, o-quinone methide formation, ring expansion, and benzofuran formation) that occur in one-pot operation under mild conditions. During these studies we also isolated surprisingly stable supports our...

The total synthesis of peniphenones A–D has been achieved via Michael reactions between appropriate nucleophiles and a common o-quinone methide intermediate. This strategy, which was based on biosynthetic hypothesis, minimized the use protecting groups thus facilitated concise syntheses natural products. most complex target, benzannulated spiroketal peniphenone A, synthesized enantioselectively in nine linear steps from commercially available starting materials.

Abstract The total synthesis of nyingchinoids A and B has been achieved through successive rearrangements a 1,2‐dioxane intermediate that was assembled using visible‐light photoredox‐catalysed aerobic [2+2+2] cycloaddition. Nyingchinoid D synthesised with competing [2+2] Based on NMR data biosynthetic speculation, we proposed structure revision the related natural product rasumatranin D, which confirmed synthesis. Under photoredox conditions, observed conversion cyclobutane into retro‐[2+2]...

The field of biomimetic synthesis seeks to apply biosynthetic hypotheses the efficient construction complex natural products. This approach can also guide revision incorrectly assigned structures. Herein, we describe evolution a concise total and structural reassignment hyperelodione D, tetracyclic meroterpenoid derived from Hypericum plant, alongside some biogenetically related products, erectones A B. key step in D forms six stereocentres three rings bioinspired cascade reaction that...

Vanadium-dependent haloperoxidases (VHPOs) from Streptomyces bacteria differ their counterparts in fungi, macroalgae, and other by catalyzing organohalogenating reactions with strict regiochemical stereochemical control. While this group of enzymes collectively uses hydrogen peroxide to oxidize halides for incorporation into electron-rich organic molecules, the mechanism controlled transfer highly reactive chloronium ions biosynthesis napyradiomycin merochlorin antibiotics sets...

Asymmetric total syntheses of (+)-azinothricin and (+)-kettapeptin have been completed through a common new pathway that exploits highly chemoselective coupling reaction between the fully elaborated cyclodepsipeptide 5 glycal activated esters 3 4 at final stages both respective syntheses.

A total synthesis of the marine sponge meroterpenoid (+)-aureol has been achieved in 12 steps (6% overall yield) from (+)-sclareolide. Key include a biosynthetically inspired sequence 1,2-hydride and methyl shifts, biomimetic cycloetherification reaction.

Abstract A five‐step total synthesis of (±)‐verrubenzospirolactone has been achieved using a biomimetic, intramolecular Diels–Alder reaction 2 H ‐chromene to form two rings and four stereocenters in the final step. This occurs spontaneously at 30 °C “on‐water”, thus suggests that it is likely be non‐enzymatic nature. The structure was also used inspire quadruple cascade generate seven stereocenters, rings, three C−C bonds, C−O bonds one

The divergence theorem is used to handle the physics required at interfaces for acoustic and elastic wave propagation in heterogeneous media. regular irregular incorporated into numerical schemes by integrating across interface. technique, which can be with many schemes, applied finite differences. A derivation of equation, readily handled this integration scheme, outlined. Since form equation equivalent scalar SH scheme also. Each component P‐SV presented apply naturally incorporating...