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The polyenoyltetramic acids pyranonigrin J (3) and pyranonigrin I (4) had been isolated from Aspergillus niger. Their origins from and roles in biosynthesis as well as the S-configurations of their stereocenter had been deduced from expression experiments with modifications of the corresponding gene cluster. We corroborated this stereochemical assignment after executing the first total syntheses of both compounds because they had essentially the same specific rotations as their natural counterparts. Our syntheses used the β-ketothioester 18 as a conjunctive reagent. It was combined with the l-serine derivatives (S)-19 or (S)-21 (“Western building blocks”), respectively, through aminolyses. Stille couplings with the stannane 13 (“Eastern building block”) followed. The resulting β-ketoamides (S)-11 and (S)-12 underwent desilylative Lacey-Dieckmann cyclizations when exposed to 8 equiv. of Bu4NF. They rendered the polyenoyltetramic acids (S)-26 [acidolysis: → (S)-3] and (S)-4, respectively.

The 5S, 8′R, and 10′R configurations of militarinone B (3), which is a natural product from Paecilomyces militaris, should equal those in its biosynthetic precursor, militarinone C. The configuration at C-1′ emerged from syntheses of the militarinone B candidates 1′′S- and 1′′R-(5S,8′R,10′R)-3 from the building blocks 9, 11, 14, and 15a while introducing TMB as a more acid-labile N-protecting group for β-ketoamides than DMB. Comparisons of 1′′S- and 1′′R-(5S,8′R,10′R)-3 with natural militarinone B (3; reisolated from Nature) revealed identity versus distinctness.

The (polyenoyl)tetramic acid militarinone C (1) heads a family of seven members. Before our work, the configuration of C-5 was unknown whereas the configurations of C-8′ and C-10′ were either (R,R) or (S,S). We synthesized the four stereoisomers of constitution 1, which conform with these insights. This included cross-coupling both enantiomers of the western building block (8) with both enantiomers of the eastern building block (9). The specific rotations of the resulting 1 isomers suggested that natural 1 is configured like the coupling partners (S)-8 and (R,R)-9. This conclusion was corroborated by degrading natural 1 to alcohol 35 and by proving its configurational identity with synthetic (R,R)-35.

SUMMARY The present invention is directed to compounds and corresponding pharmaceutical formulations for use in the medical treatment of CNS- and neurodegenerative diseases, for example, for use in the treatment and prophylaxis of familial or sporadic Alzheimer's disease. The invention further relates to corresponding methods of treatment.

The present invention is directed to cell-protective, in particular, cardio- and renal-protective organic compounds, preferably to organic compounds that inhibit substrate phosphorylation by the G-protein-coupled receptor kinase 2 (GRK2, ADRBK1). Preferably, the organic compounds inhibit the GRK2-mediated phosphorylation of serine/arginine-rich splicing factor 1 (SRSF1, ASF- 1, SF2) and/or phosducin for treating hypertension, heart diseases, heart dysfunction or failure and heart disease-associated pathologies, e.g. cardiomyocyte necrosis, ischemic cardiac disease and/or ischemic heart damage or ageing. Furthermore, the present invention is directed to a method for the identification of inhibitors of the (GRK2)-mediated phosphorylation of (SRSF1) and/or phosducin.

Ph3P, Br2, and ammonium acetate are used for the in situ generation of Ph3P(OAc)2, which was characterized by different NMR techniques. The Ph3P(OAc)2generated was used as a novel and efficient reagent for the acetylation of alcohols and thiols in acetonitrile at room temperature under homogeneous conditions. This reaction was also performed under heterogeneous conditions using 1,3,2,4- diazadiphosphetidine as an easily prepared, stable, and heterogeneous P(III) compound.

Carboxylic esters and thioacetates were conveniently prepared in good to excellent yields under mild conditions by the reaction of alkyl halides with sodium carboxylates or sodium thioacetate catalyzed by PEG400 in the absence of solvents. Copyright Taylor & Francis Group, LLC.

(Chemical Equation Presented) Among six different group VIb oxometallic species examined, dioxomolybdenum dichloride and oxomolybdenum tetrachloride were the most efficient catalysts to facilitate nucleophilic acyl substitution (NAS) of anhydrides with a myriad array of alcohols, amines, and thiols in high yields and high chemoselectivity. In contrast to the well-recognized redox chemical behaviors associated with oxomolybdenum(VI) species, the catalytic NAS was unprecedented and tolerates virtually all kinds of functional groups. By using benzoic anhydride as a mediator for in situ generation of an incipient mixed anhydride-MoO2Cl2 adduct with a given functional alkanoic acid, one can achieve oleate, dipeptide, diphenylmethyl, N-Fmoc-α-amino, pyruvic, and tert-butylthio ester, N-tert-butylamide, and trityl methacrylate syntheses with appropriate protic nucleophiles. The amphoteric character of the Mo=O unit in oxomolybdenum chlorides was found to be responsible for the catalytic NAS profile as supported by a control NAS reaction of using an authentic adduct-MoOCl2(O2-CBu t)2 between pivalic anhydride and MoO2Cl 2 as the catalyst.

Thioacetates are conveniently prepared in high yields under mild conditions by the reaction of alkyl halides and sodium thioacetate, prepared in situ from thioacetic acid and sodium carbonate, catalysed by PEG400 at room temperature.

Figure presented Among four vanadyl species examined, vanadyl triflate was the most efficient catalyst to facilitate nucleophilic acyl substitution of anhydrides with a myriad array of alcohols, amines, and thiols in high yields and high chemoselectivity. By using mixed-anhydride technique, one can achieve oleate and peptide syntheses. In marked contrast to common metal Inflates, the amphoteric character of the V=O unit in vanadyl species was proven to be responsible for the catalytic profile in this process.

Exposure of α-diazo thiol esters (1) to the action of catalytic rhodium(II) acetate leads to a remarkably facile "thia-Wolff rearrangement", producing thio-substituted ketenes which combine with a variety of ketenophiles to provide access to α-thiocyclobutanones, cyclobutenones, and β-lactams. Reductive desulfurization of these cycloadducts takes place under mild conditions and in excellent yield, and this sequence thus represents a useful new alternative to the existing dichloroketene-based methodology for the synthesis of four-membered carbocycles and heterocycles.

Tertiary alkyl, allylic and benzylic halides react with zinc thiolacetate, prepared in situ, under optimised conditions to yield the corresponding thiolacetates in moderate to good yields.

Novel imidazoles of the formula STR1 and their non-toxic, pharmaceutically acceptable salts with acids and bases having an antagonistic activity against angiotensin II receptors.

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A variety of alkyl halides including tertiary alkyl halides react smoothly with the zinc salts of thiols and thiolcarboxylic acids yielding thioethers and thiolesters.

Alkane- (or arene)-thiols or thiolates add smoothly to esters or amides of 1-methylpyridinium-3,5-dicarboxylic acid salts; on treatment of these adducts with activated acid-derivatives, thioesters are formed in excellent yields.