Reactivity of 1-methylisoquinoline synthesis of pyrazolyl triazoloisoquinoline and thia-diazolyl isoquinoline derivatives

The reaction of 1-methylisoquinoline 1 with hy-drazonoyl halides 2 in ethanol in the presence of chitosan under microwave irradiation affords triazoloisoquinoline 4. Product 4 reacts with dimethylformamide-dimethylacetal to give ena- minones 7 which react with hydrazonoyl halides to give pyrazolyl triazoloisoquinoline 13. Also, 1-methylisoquinoline 1 reacts with arylisothio-cyanate to give thioanilide 15 which reacts with hydrazonoyl halides to give the corresponding thiadiazolyl isoquinoline derivatives 20, 24.

Analysis of isoquinoline alkaloids from Mahonia leschenaultia and Mahonia napaulensis roots using UHPLC-Orbitrap-MSn and UHPLC-QqQ LIT-MS/MS

Mahonia leschenaultia(ML) and Mahonia napaulensis(MN) are less known and unexplored medicinal plants of the family Berberidaceae. They are used by the Todas of Nilgiris in their religious and medical practices but chemically less identified. Hence, we decided to do extensive phytochemical analysis to explore the potential of these plant extracts. An ultrahigh performance electrospray tandem mass spectrometry(UHPLC–ESI–MS/MS)method was successfully developed for qualitative analysis of the bioactive components in Mahonia species using Orbitrap Velos Pro mass spectrometer. Sixteen compounds were identified by comparison of their retention times and mass spectra(MS) with authentic standards and reported literature. Multi-stage mass spectra(MS^(2–8)) for the identification of protoberberine and aporphine alkaloids showed the sequential expulsion of all the substituents attached with their basic skeleton followed by CO loss. Eight of the identified compounds(berberine, jatrorrhizine, palmatine, magnoflorine, isocorydine, glaucine, tetrahydropalmatine and tetrahydroberberine) were simultaneously determined by another UHPLC–ESI–MS/MS method under the multiple reactions monitoring(MRM) mode quantitatively using triple quadrupole linear ion trap mass spectrometer. The analytical method was validated for 8 bioactive compounds with overall recovery in the range98.5%–103.6%(RSD≤2.2%), precise(RSD≤2.07%) and linear(r≥0.9995) over the concentration range of 0.5–1000 ng/mL and successfully applied in ML and MN roots, which suggests the suitability of the proposed approach for the routine analysis of Mahonia species and their quality control.

Amides,Isoquinoline Alkaloids and Dipeptides from the Aerial Parts of Piper mullesua

One undescribedamide,pipermullesine A,twoundescribed isoquinoline alkaloids,pipermullesinesBand C,and six undescribed dipeptides,pipermullamides A–F,along with 28 known compounds,were isolated from the aerial parts of Piper mullesua.The structures of the undescribed compounds were elucidated based on the analysis of 1D and 2D NMR and MS data.Furthermore,the structures of pipermullesines A–Cwere confirmed by single crystal X-ray diffraction analysis.All isolates were evaluated for inhibitory activity against platelet aggregation induced by thrombin(IIa)or platelet-activating factor(PAF).(-)-Mangochinine,pellitorine,and(2E,4E)-N-isobutyl-2,4-dodecadienamide showed weak inhibitory activity against rabbit platelet aggregation induced by PAF,with IC_(50)values of 470.3μg/mL,614.9μg/mL,and 579.7μg/mL,respectively.

Synthesis and Pregnancy Terminating Activity of 2-Aryl imidazo [2,1-a] isoquinolines

Two 2-aryl imidazo [2,1-a] isoquinolines were synthesized and tested for pregnancy terminating activities. Both of them are new compounds and their structures were confirmed by IR, 1HNMR, MS and elemental analysis. They both showed high activities in NIH mice.

Radical cascade cyclization for the green and simple synthesis of silylated indolo[2,1-a]isoquinoline derivatives via visible light-mediated Si–H bonds activation

Photocatalytic and photoinduced silyl radicals cascade cyclization procedures for the green and simple preparation of fused tetracyclic skeleton silylated indolo[2,1-a]isoquinoline-6(5H)-ones from 2-aryl-N-acryloyl indoles with hydrosilanes are developed.The photocatalytic reaction is carried out with 9,10-dicyanoanthracene(DCA)as an organophotocatalyst and 3-acetoxyquinuclidine as hydrogen atom transfer(HAT)catalyst at room temperature under metal-and oxidant-free conditions.The keys to the success of photoredox-catalytic conversion include(1)the reductive quenching of DCA^(*)[E_(1/2)(*P/P^(-))=+1.97 V vs.SCE in MeCN]by 3-acetoxyquinuclidine(E_(p)=+1.22 V vs.SCE in MeCN),and(2)the thermodynamic feasibility of hydrogen atom abstraction from hydridic Si-H bond by electrophilic N^(+·).Particularly,the simple photoinduced cascade cyclization using(TMS)3SiH with 2-aryl-N-acryloyl indoles was exploited via an electron-donor-acceptor(EDA)complex under visible light irradiation.

Effects of Metal Cations and Counter Anions on the Structural Stability of Isoquinoline-Based Metallo-Supramolecular Cages

Metallo-supramolecular architectures that are constructed by coordination-driven self-assembly have received tremendous attention on account of their diverse yet molecular-level precise structures and broad applications.Of particular,metal cations and counter anions are fundamentally important in terms of self-assembly,characterization and property;however,their effects on the structural stabilities of metallo-supramolecular architectures have seldom been investigated.To address this issue,herein,a series of octahedral metallo-cages that are capable of tolerating with five metal cations(Pd^(2+),Cu^(2+),Ni^(2+),Co^(2+)and Zn^(2+)),and five counter anions(ClO_(4)^(–),OTf^(–),BF_(4)^(–),NTf_(2)^(–)and NO_(3)^(–))are constructed by the coordination-driven self-assembly of a well-designed tritopic isoquinoline-based ligand with corresponding metal salts.Structural stability studies show that metal cations and counter anions play a critical role in the stability of the resulting cages depending on their coordination abilities and stacking manners.This work provides deep insights in the ever-diversifying field of metallo-supramolecular chemistry,and will enable us to design more sophisticated assembled structure with desired function.

Palladium-catalyzed carbonylative cyclization of alkene-tethered indoles with phenols or arylboronic acids:Construction of carbonyl-containing indolo[2,1-a]isoquinoline derivatives

A novel palladium-catalyzed carbonylative cyclization of alkene-tethered indoles with phenols or arylboronic acids is described,which provides a facile approach to access indolo[2,1-a]isoquinoline scaffolds.This method employs benzene-1,3,5-triyl triformate(TFBen)as the CO surrogate for the incorporation of a carbonyl group into indolo[2,1-a]isoquinoline scaffolds,and a variety of carbonyl-containing indolo[2,1-a]isoquinoline derivatives are prepared in good yields.

Pd(II)and Rh(III)Complexes with Isoquinoline Derivatives Induced Mitochondria-Mediated Apoptotic and Autophagic Cell Death in HepG2 Cells

Nonplatinummetal complexes of[Pd(L^(1))Cl_(2)](C1),[Rh(L^(1))Cl_(3)(DMSO)](C2),[Pd(L^(2))Cl_(2)](C3),and[Rh(L^(3))Cl_(3)(DMSO)](C4)with isoquinoline derivatives have been prepared and characterized.C1-C4 exhibited higher in vitro anticancer activity and lower toxicity than the corresponding ligands and cisplatin against HepG2 cells.The mechanistic studies revealed that C1 arrested the cell cycle at S-phase by regulation of cyclin and cyclin-dependent kinases.C1 was accumulated in mitochondria,which increased the generation of reactive oxygen species(ROS)and endoplasmic reticulum(ER)-stress response through mitochondrial dysfunction.Moreover,C1 stimulated Ca^(2+)release,activated the caspase cascade,and triggered mitochondria-mediated apoptosis.The in vivo studies of C1 demonstrated higher safety than cisplatin and effective tumor growth inhibition.C1 is a potential anticancer drug candidate.

Novel Total Synthesis of Mansouramycin B

Mansouramycin B (1 ) 的新奇全部的合成在从容易地可得到、便宜的 salicylaldehyde 开始的 28% 全面产量经由 10 步被执行。这全部的合成的二关键步是引人注目的。第一个是支持底的一个壶 N-tosyltetrahydroisoquinoline 6 的氧气的 aromatization，第二是 5-hydroxy-3-methyl-isoquinoline 的氧化 8 与 iodobenzene diacetate [PhI (OAc )2] 。

Design and synthesis of unique thiazoloisoquinolinium thiolates and derivatives

Natural isoquinolinium alkaloids possess a wide range of biological activities.The design and synthesis of mesoionic isoquinoliniums is of great importance.This paper reports the synthesis of unique mesoionic thiazoloisoquinolinium thiolates stabilized by aromatization and 1,3-dipolarization.Such compounds can be synthesized via the three component [2 + 2 + 1] cycloaddition reaction of isoquinolines with ethyl propionate and elemental sulfur in the absence of any metal catalyst and additives.Importantly,thiazoloisoquinolinium thiolates can be transformed to thioether-containing thiazoloisoquinolinium halides.A selective [4 + 2] cycloaddition can also be used to form S-bridged fused tetracyclic compounds with a thiothiamide ring unit and two quarternary carbon centres.Compound I-1 shows good bioactivity against the chlorophyll of duckweed(Lemna minor) with inhibition rate of 51.5 mg/mL.

Alkaloid Dimers Isolated from Thalictrum baicalense Have Antitumor Activities

Comprehensive Summary A pair of heterodimeric isoquinoline alkaloid enantiomers,(+)thaliberberine A,five new thalifaberine-type aporphine-benzylisoquinoline(ABl)alkaloids,thalicultratines M-Q,and thirteen known analogues were isolated from the roots of Thalictrum baicalense Turcz.ex Ledeb.The structures were determined by extensive spectroscopic methods and ECD calculations.Thaliberberine A featuring a novel carbon skeleton coupled by two different classes of isoquinoline alkaloids,protoberberine and phthalidoisoquinoline,represents the first natural product with the berberine skeleton substituted at C-6.Plausible biosynthetic routes of 1 are proposed.

Diversity-oriented synthesis of blue emissive nitrogen heterocycles and their conjugation with carbon nano-onions

The search for new fluorescent molecules for possible applications as functional p-electron systems and their conjugation with different nanomaterials is nowadays of paramount importance to broaden the availability of materials with different properties.Herein we present a diversity-oriented approach to heterocyclic luminophores based on a multicomponent Ugi reaction followed by a Pd-mediated cascade sequence.The new molecules are coupled to carbon nano-onions,and hybrid systems represent the first example of blue emitters conjugated with these carbon nanoparticles.