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Parkinson's disease is a chronic and progressive neurodegenerative disease, induced by slow and progressive death of the dopaminergic (DA) neurons from the midbrain region called substantia nigra (SNc) leading to difficulty in locomotion. At present, very few potential therapeutic drugs are available for treatment, necessitating an urgent need for development. In the current study, the parkin transgenic Drosophila melanogaster model that induces selective loss in dopaminergic neurons and impairment of locomotory functions has been used to see the effect of the aza-flavanone molecule. D. melanogaster serves as an amazing in vivo model making valuable contribution in the development of promising treatment strategies. Our in-silico study showed spontaneous binding of this molecule to the D2 receptor making it a potential dopamine agonist. PARKIN protein is well conserved, and it has been reported that Drosophila PARKIN is 42% identical to human PARKIN. Interestingly, this molecule enhances the motor coordination and survivability rate of the transgenic flies along with an increase in expression of the master regulator of Dopamine synthesis, that is, tyrosine hydroxylase (TH), in the substantia nigra region of the fly brain. Moreover, it plays a significant effect on mitochondrial health and biogenesis via modulation of a conserved mitochondrial protein PHB2. Therefore, this molecule could lead to the development of an effective therapeutic approach for the treatment of PD.

Adamantan-1-yl 1-pentyl-1H-indazole-3-carboxylate (APINAC), a new synthetic cannabinoid, was recently isolated from a dietary supplement and identified in our laboratories. The metabolism and pharmacokinetics of APINAC were studied in vitro and in vivo with a rat model. APINAC (2.0 μM) was incubated with rat liver microsomes (RLMs) for up to 90 min to determine its phase I metabolic profile. APINAC was also administered to rats at a dose of 5 mg/kg intravenously (i.v.) or 10 mg/kg per os (p.o.). Blood samples were collected at specific time points, and urine samples were also collected for 1 day following APINAC administration. The analyses were conducted by both high- and low-resolution liquid chromatography–tandem mass spectrometry. Although APINAC was rapidly metabolized by RLMs (t 1/2, 15.2 ± 0.4 min), in vivo pharmacokinetic experiments in rats revealed moderate to long half-lives [11.3 h (i.v.) and 3.8 h (p.o.)]. A total of 22 APINAC metabolites could be detected in the RLMs and rat urine. APINAC was predominantly metabolized via ester hydrolysis to carboxylic acids M1 (with hydroxylation) and M18 (without hydroxylation), representative markers for APINAC intake. Hydroxylation of APINAC, with or without subsequent oxidation and glucuronidation, was observed in the case of the other metabolites. The diagnosis of illegal APINAC intake can be realized through the detection of several characteristic APINAC metabolites in human urine and/or APINAC itself in blood.

A convergent and stereoselective approach for the synthesis of C1-C11, C12-C22, and C23-C28 fragments of cytotoxic natural products cruentaren A and B are accomplished. Highlights of the strategy include a Sharpless epoxidation followed by a regioselective opening of epoxide to generate anti and syn -stereochemistry at C9-C10 and C15-C16, an Alder-Rickert reaction between a 1,5-dimethoxy-1,4-cyclohexadiene and dienophile to construct the aromatic ring, and a lithium-mediated aldol reaction to install the C17-C18 anti -stereochemistry. The synthesis of C1-C11 and C12-C22 fragments proceed with a longest linear sequence of 10 and 17 steps from commercially available 2-butyne-1,4-diol and cis -2-butene-1,4-diol respectively.

A number of phosphodiesterase 5 (PDE5) inhibitors approved by authorities have been used successfully in the treatment of erectile dysfunction. These medicines must be prescribed carefully due to their adverse effects, but they and their analogues are being illegally added to dietary supplements. These illegal dietary supplements pose a significant risk to public health. Several dimeric tadalafil analogues have been synthesized for use as reference standards in the inspection of functional foods that are mainly advertised as sexual enhancement products. During the course of this synthesis, 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxid hexafluorophosphate (HATU) was proven to be the reagent of choice for amide coupling to produce these dimeric tadalafil analogues. Moreover, the trans-isomer structures tentatively assigned for the isolated dimeric tadalafil analogues (bisprehomotadalafil and bisprecyclopentyltadalafil) found in dietary supplements are now revised to cis-isomer structures.

A new tadalafil analogue was found, along with nortadalafil, using HPLC-DAD during the inspection of a health product sold without official approval. The analogue was separated using a semi-preparative HPLC system and its structure was determined by a combination of mass spectrometry and NMR spectroscopy. The compound was identified as a tadalafil analogue in which the N-methyl group of tadalafil was replaced with a tadalafil precursor moiety. Nuclear Overhauser effect spectroscopy experiments suggested a cis-relationship between the substituents on a piperidine ring in the tadalafil moiety.

A concise stereoselective total synthesis of cryptomoscatone F1 has been accomplished by utilization of asymmetric acetate aldol reaction, Brown’s asymmetric allylation, and olefin cross-metathesis as key transformations.

The first stereoselective total synthesis of the proposed structure of the γ-lactone from Diaporthe sp. SXZ-19 was achieved by utilizing a convergent pathway. The four stereogenic centers were formed by employing Brown's asymmetric alkoxyallylboration reaction, and a cross-metathesis reaction was used to construct the trans double bond of the γ-lactone side chain. This synthesis led to a revision of proposed structural assignment of the natural product.

Lung cancer accounts for the highest death rate among cancers worldwide, with most patients being diagnosed with non-small cell lung cancer (NSCLC), urging more effective therapies. We report that JK273, a pyrrolo[2,3-d]pyrimidine analog, which inhibits α4 integrin signaling, showed a selective cytotoxic effect against HCI-H460 NSCLC cells, with an IC50 of 0.98 ± 0.15 μM, but showed less sensitivity to fibroblasts with a selectivity index (SI) greater than 30. This effect was attributed to cell cycle arrest at S phase by JK273 treatment, resulting in the apoptosis of NCI-H460 cells, further confirmed by exposing phosphatidylserine and morphological changes. Taken together with the previous study of JK273 inhibiting cell migration, we propose that JK273 could serve as an antitumor compound to specifically target cancer cells but not non-cancerous cells by triggering programmed cell death, in addition to anti-metastatic effects in cancer therapy.

A concise stereoselective total synthesis of cryptomoscatone F1 has been accomplished by utilization of asymmetric acetate aldol reaction, Brown’s asymmetric allylation, and olefin cross-metathesis as key transformations.

The total synthesis of (+)-(6R,2′S)-cryptocaryalactone and (−)-(6S,2′S)-epi cryptocaryalactone is reported based on asymmetric acetate aldol reaction. Still–Gennari reaction, Evans acetal intramolecular oxa-Michael reaction and lactonisation are the key steps in the target synthesis.

An efficient concise stereoselective total synthesis of cryptomoscatone D2 and syntheses of (5R,7S)-kurzilactone and (+)-cryptofolione, based on an asymmetric acetate aldol reaction starting from trans-cinnamaldehyde, are described. The other key reactions are a Horner–Wadsworth–Emmons reaction, a Brown’s asymmetric allylation and a ring-closing metathesis.

aza-Flavanones have been identified as a new class of selective microRNA inhibitors. These compounds were found to arrest cell cycle via a novel cross species microRNA-dependent regulatory pathway interpreting an unexpected link between cell cycle arrest and microRNA mediated control in cancer.

Total syntheses of the natural products (Ia,b) are described for the first time leading to the structural revision of the previously proposed assignment of compound (Ia).

The first total synthesis of (S)-6-(2,9-dihydroxynonyl)-4-hydroxy-3-methyl-2H-pyran-2-one, 4-hydroxy-3-methyl-6-((2S,4R)-2,4,11-trihydroxyundecyl)-2H-pyran-2-one, and its unnatural 2R,4R-isomer starting from commercially available 1,8-octanediol is described. The synthesis led to the revision of the proposed structural assignment of the natural product as (R)-6-(2,9-dihydroxynonyl)-4-hydroxy-3-methyl-2H-pyran-2-one. The key steps include chiral auxiliary mediated asymmetric acetate aldol reaction, dianion addition, and base mediated cyclization to form an α-pyrone ring.

A facile stereoselective total synthesis of secondary metabolite (+)-polyrhacitide A is described. Stereoselective aldol reaction, Horner–Wardsworth–Emmons reaction, Evans acetal intramolecular oxa-Michael reaction and diastereoselective syn reduction reaction are the key steps involved in the target synthesis.

An efficient cleavage of methoxy methyl ether using NbCl5 is described. This protocol works efficiently with MOM ethers of alkyl, allyl, propargyl, benzyl alcohol and phenol derivatives. MOM esters are also found to be effectively cleaved under the present conditions.

Formal total synthesis of cyanolide A, aglycosidic dimeric macrolide is accomplished. The key reactions involved are asymmetric acetate aldol reaction, CBS reduction, and Shiina's lactonization.

An efficient cleavage of methoxy methyl ether using NbCl5 is described. This protocol works efficiently with MOM ethers of alkyl, allyl, propargyl, benzyl alcohol and phenol derivatives. MOM esters are also found to be effectively cleaved under the present conditions.

A stereoselective total synthesis of (+)-goniothalamin and cryptomoscatone E1 have been described. The synthetic strategy involves an asymmetric acetate aldol reaction, Evans acetal intramolecular oxa-Michael reaction, ring-closing metathesis, Horner–Wadsworth–Emmons reaction and lactonization as the key steps.