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1.
Four new pyrrole alkaloids, methyl 2‐[2‐formyl‐5‐(methoxymethyl)‐1H‐pyrrol‐1‐yl]propanoate ( 1 ), methyl 2‐[2‐formyl‐5‐(methoxymethyl)‐1H‐pyrrol‐1‐yl]‐3‐(4‐hydroxyphenyl)propanoate ( 2 ), dimethyl 2‐[2‐formyl‐5‐(methoxymethyl)‐1H‐pyrrol‐1‐yl]butanedioate ( 3 ), and dimethyl 2‐[2‐formyl‐5‐(methoxymethyl)‐1H‐pyrrol‐1‐yl]pentanedioate ( 4 ), were isolated from the AcOEt extract of the fruits of Lycium chinense Miller (Solanaceae). The stereogenic center C(2) in the bulky N‐alkyl side chain in each of 1 – 4 seems to hold the H‐atoms of nearby CH2 groups, CH2(7′) and CH2(3) (if R≠H), leading to two different chemical shifts in the 1H‐NMR spectrum due to their diastereotopic characteristics. In the 1H‐NMR data of each of 2 – 4 , the enhancement of H? C(2) signal was inhibited by the R group, probably due to steric hindrance, and its chemical shift was influenced by the anisotropy effect. The structures of 1 – 4 were elucidated by analysis of various spectroscopic data, including 1D‐ and 2D‐NMR.  相似文献   

2.
Acotoxinine ( 1 ), a new norditerpene alkaloid, was isolated from the roots of Aconitum toxicum Rchb ., together with the structurally related C19 diterpene alkaloids neoline ( 2 ) and aconitine ( 3 ) and C20 diterpene alkaloids songorine ( 4 ) and songoramine ( 5 ). The structures were elucidated by HR‐MS and advanced NMR methods, including 1H‐NMR, JMOD, 1H,1H‐COSY, HSQC, and HMBC experiments. This is the first report of C20 diterpenoid alkaloids in Aconitum toxicum.  相似文献   

3.
The phytochemical investigations on Cleome droserifolia resulted in the isolation and characterization of a new indole alkaloid, 5‐hydroxy‐2‐methoxy‐1‐methyl‐1H‐indole‐3‐carbaldehyde ( 1 ). The structure elucidation was carried out on the basis of 1D‐ and 2D‐NMR techniques. In addition to 1 , two known aromatic derivatives, veratrol ( 2 ) and 2‐methoxy‐4‐methylacetophenone ( 3 ), were also obtained. All these compounds were purified by repeated column chromatography of the CH2Cl2 fraction obtained from MeOH extract of Cleome droserifolia. The structure of the new compound 1 was finally confirmed by the combined 1D (1H‐ and 13C‐) and 2D (H? C correlations; HMBC and HSQC) NMR and IR spectroscopy, mass spectrometry (MS), and UV absorption spectroscopy techniques. The comparison of the physical and spectroscopic data with those in the literature provided evidence for the structure confirmation of known compounds. All the purified compounds were subjected to urease and α‐glucosidase enzymes inhibition. The results showed that compound 1 was more potent with an IC50 value 11.97±2.067 μg/ml towards urease inhibition, while the activity of α‐glucosidase enzyme was marginal.  相似文献   

4.
Five new C19 diterpene alkaloids, leucanthumsines A ( 1 ), B ( 2 ), C ( 3 ), D ( 4 ), and E ( 5 ), were isolated from the Chinese medicinal herb Aconitum sungpanense var. leucanthum, together with the known C19 diterpene alkaloids pseudaconine, neoline, 1‐O‐methyldelphisine, crassicaudine, chasmanine, talatisamine, indaconitine, ezochansmanine, and leueantine D. The structures of these new alkaloids were elucidated by HR‐MS and advanced NMR methods, including 1H‐ and 13C‐NMR (DEPT), 1H,1H‐COSY, HMQC, and HMBC experiments.  相似文献   

5.
Two new C20‐diterpenoid alkaloids named naviculine A ( 1 ) and naviculine B ( 2 ), were isolated from Aconitum naviculare Stapf . Their structures were established by spectral methods, especially 2D‐NMR spectra (1H,1H‐COSY, HMQC, HMBC, and NOESY) and DFT methods (at the B3LYP/6‐311++G(2d,p)//B3LYP/6‐31G(d) level), respectively. They were assayed for their anti‐HIV‐1 activity.  相似文献   

6.
Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis. Among them, yunnanensine (I) is new. The other five are known alkaloids, namely: 19,20-E-vallesamine (II), 19s-heyneanine (HI), ibogaine (IV), ibogamine (V), coronaridine (VI). The structural elucidation of the alkaloids was based on spectral means.  相似文献   

7.
A new lycopodine alkaloid, 15α‐methyllycopodane‐5β,6β‐diol N‐oxide ( 1 ), was isolated from the whole plants of Phlegmariurus yunnanensis Ching , together with the two known alkaloids 15α‐methyllycopodane‐5β,6β‐diol ( 2 ) and lycoposerramine H ( 3 ), and four serratene‐type triterpenoids, serratenediol‐3‐acetate ( 4 ), serratenediol ( 5 ), lycocryptol ( 6 ), and serratriol ( 7 ). Their structures were elucidated on the basis of spectroscopic analyses, including HR‐ESI‐MS, 1H‐ and 13C‐NMR, DEPT, 1H,1H‐COSY, HSQC, HMBC, and NOESY.  相似文献   

8.
From the aerial parts of Delphinium buschianum Grossh ., collected in Turkey, a new diterpenoid alkaloid 1 , named budelphine, was isolated along with the known diterpenoid alkaloids karakoline ( 2 ), 18‐hydroxy‐14‐O‐methylgadesine ( 3 ), delsoline ( 4 ), lapaconidine ( 5 ), columbianine ( 6 ), 14‐benzoylneoline ( 7 ), and hetisine ( 9 ). The structure of 1 was established on the basis of 1H‐, 13C‐, DEPT, 1H,1H‐COSY, NOESY, HSQC, and HMBC NMR studies.  相似文献   

9.
A phytochemical study on Borreria verticillata has led to the isolation of two novel simple indole alkaloids, 6‐methoxy‐4‐(3‐methylbut‐2‐en‐1‐yl)‐1H‐indole, named verticillatine A ( 1 ), and 1‐(1H‐indol‐6‐yl)‐3‐methylbutan‐1‐one, named verticillatine B ( 2 ), one new iridoid, 6′‐O‐(2‐glyceryl)scandoside methyl ester ( 3 ), with the glycerol unit linked to a glucose unit, and two known ones, asperuloside ( 4 ) and scandoside methyl ester ( 5 ). The structures of these compounds were elucidated on the basis of spectroscopic‐data analyses, mainly 1H‐ and 13C‐NMR, including 2D experiments (1H,1H‐COSY, NOESY, HMBC, and HMQC), and HR‐ESI‐MS.  相似文献   

10.
《化学:亚洲杂志》2017,12(2):239-247
Five bis(quinolylmethyl)‐(1H ‐indolylmethyl)amine (BQIA) compounds, that is, {(quinol‐8‐yl‐CH2)2NCH2(3‐Br‐1H ‐indol‐2‐yl)} ( L1H ) and {[(8‐R3‐quinol‐2‐yl)CH2]2NCH(R2)[3‐R1‐1H ‐indol‐2‐yl]} ( L2–5H ) ( L2H : R1=Br, R2=H, R3=H; L3H : R1=Br, R2=H, R3=i Pr; L4H : R1=H, R2=CH3, R3=i Pr; L5H : R1=H, R2=n Bu, R3=i Pr) were synthesized and used to prepare calcium complexes. The reactions of L1–5H with silylamido calcium precursors (Ca[N(SiMe2R)2]2(THF)2, R=Me or H) at room temperature gave heteroleptic products ( L1, 2 )CaN(SiMe3)2 ( 1 , 2 ), ( L3, 4 )CaN(SiHMe2)2 ( 3 a , 4 a ) and homoleptic complexes ( L3, 5 )2Ca ( D3 , D5 ). NMR and X‐ray analyses proved that these calcium complexes were stabilized through Ca⋅⋅⋅C−Si, Ca⋅⋅⋅H−Si or Ca⋅⋅⋅H−C agostic interactions. Unexpectedly, calcium complexes (( L3–5 )CaN(SiMe3)2) bearing more sterically encumbered ligands of the same type were extremely unstable and underwent C−N bond cleavage processes as a consequence of intramolecular C−H bond activation, leading to the exclusive formation of (E )‐1,2‐bis(8‐isopropylquinol‐2‐yl)ethane.  相似文献   

11.
Hermidin ( 1 ), a piperidine‐2,3‐dione alkaloid, has been previously detected as a lipophilic constituent in Mercurialis perennis L. and other Mercurialis species. Because of strong electron‐withdrawing effects of its carbonyl groups, an acidic H‐atom is easily subtracted from 1 , whereas the latter shows high reactivity towards oxidation reactions or the attack of C‐nucleophilic agents. To obtain a better understanding of possible chemical pathways upon extraction of root parts of M. perennis, the products obtained with different solvents from 1 were investigated. Extraction of M. perennis with aqueous MeOH or EtOH yielded a mixture of hermidin quinone ( 3 ), 5‐hydroxy‐4‐methoxy‐5‐(alkoxycarbonyl)‐1‐methyl‐3‐pyrrolin‐2‐ones, 7 and 8 , and d,l‐ and meso‐isochrysohermidins, 5 and 6 , all of them being investigated by GC/MS and LC/MSn. The latter compounds were supposedly formed by free‐radical reactions, followed by spontaneous benzilic acid rearrangement and esterification. Furthermore, extraction of M. perennis with aqueous Me2CO produced an aldol condensation product, the known alkaloid speranskatine A ( 9a ), which was identified by NMR after chromatographic purification. In a similar manner, a CH2 homolog of speranskatine A ( 10a ) was obtained as a novel compound when ethyl methyl ketone (=butan‐2‐one; EtCOMe) instead of Me2CO was used for extraction. Consequently, 1 easily undergoes artefact formation upon extraction of plant material with polar or slightly polar solvents.  相似文献   

12.
The NMR spectral analysis of voacangine hydroxyindolenine ( 2 ) and of some synthetic derivatives, together with mechanistic considerations, permitted to establish its absolute configuration at C(7) as (R). The configuration at C(7) in hydroxyindolenines of the ibogamine series is also discussed and would be (S).  相似文献   

13.
Reactions of bis(phosphinimino)methanes H2C(PPh2NR)2 [R = SiMe3 (L1H), Ph (L2H), 2,6‐iPr2‐C6H3 (DIPP) (L3H)] with ZnR2 (R = Me, Et) yielded the corresponding bis(phosphinimino)methanide zinc complexes LZnMe [L2 ( 1 ), L3 ( 2 )] and LZnEt [L1 ( 3 ), L2 ( 4 ), and L3 ( 5 )]. Complexes 1 – 5 were characterized by heteronuclear NMR (1H, 13C, 31P) and IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction.  相似文献   

14.
1H and 13C NMR assignments for 1a–4a and 1b–4b were obtained using HSQC, HMBC and NOESY techniques. Differences and ambiguities from literature assignments are reconciled. For the pyrrolidine C‐ring, the combined use of NMR spectroscopy and molecular mechanics calculations revealed that this ring exists in a dynamic conformational equilibrium between twist (2T1) and envelope‐twist (1E–1T2) conformations. In chloroform‐d1, the 1H NMR coupling constants indicate that the pyrrolidine ring is biased in favor of the envelope‐twist conformation. Steric requirements of the N‐prenyl group enhanced the envelope‐twist (1E–1T2) conformation populations. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

15.
Three new metal(II)–cytosine (Cy)/5‐fluorocytosine (5FC) complexes, namely bis(4‐amino‐1,2‐dihydropyrimidin‐2‐one‐κN3)diiodidocadmium(II) or bis(cytosine)diiodidocadmium(II), [CdI2(C4H5N3O)2], ( I ), bis(4‐amino‐1,2‐dihydropyrimidin‐2‐one‐κN3)bis(nitrato‐κ2O,O′)cadmium(II) or bis(cytosine)bis(nitrato)cadmium(II), [Cd(NO3)2(C4H5N3O)2], ( II ), and (6‐amino‐5‐fluoro‐1,2‐dihydropyrimidin‐2‐one‐κN3)aquadibromidozinc(II)–6‐amino‐5‐fluoro‐1,2‐dihydropyrimidin‐2‐one (1/1) or (6‐amino‐5‐fluorocytosine)aquadibromidozinc(II)–4‐amino‐5‐fluorocytosine (1/1), [ZnBr2(C4H5FN3O)(H2O)]·C4H5FN3O, ( III ), have been synthesized and characterized by single‐crystal X‐ray diffraction. In complex ( I ), the CdII ion is coordinated to two iodide ions and the endocyclic N atoms of the two cytosine molecules, leading to a distorted tetrahedral geometry. The structure is isotypic with [CdBr2(C4H5N3O)2] [Muthiah et al. (2001). Acta Cryst. E 57 , m558–m560]. In compound ( II ), each of the two cytosine molecules coordinates to the CdII ion in a bidentate chelating mode via the endocyclic N atom and the O atom. Each of the two nitrate ions also coordinates in a bidentate chelating mode, forming a bicapped distorted octahedral geometry around cadmium. The typical interligand N—H…O hydrogen bond involving two cytosine molecules is also present. In compound ( III ), one zinc‐coordinated 5FC ligand is cocrystallized with another uncoordinated 5FC molecule. The ZnII atom coordinates to the N(1) atom (systematic numbering) of 5FC, displacing the proton to the N(3) position. This N(3)—H tautomer of 5FC mimics N(3)‐protonated cytosine in forming a base pair (via three hydrogen bonds) with 5FC in the lattice, generating two fused R22(8) motifs. The distorted tetrahedral geometry around zinc is completed by two bromide ions and a water molecule. The coordinated and nonccordinated 5FCs are stacked over one another along the a‐axis direction, forming the rungs of a ladder motif, whereas Zn—Br bonds and N—H…Br hydrogen bonds form the rails of the ladder. The coordinated water molecules bridge the two types of 5FC molecules via O—H…O hydrogen bonds. The cytosine molecules are coordinated directly to the metal ion in each of the complexes and are hydrogen bonded to the bromide, iodide or nitrate ions. In compound ( III ), the uncoordinated 5FC molecule pairs with the coordinated 5FC ligand through three hydrogen bonds. The crystal structures are further stabilized by N—H…O, N—H…N, O—H…O, N—H…I and N—H…Br hydrogen bonds, and stacking interactions.  相似文献   

16.
Cardiosulfa is a biologically active sulfonamide molecule that was recently shown to induce abnormal heart development in zebrafish embryos through activation of the aryl hydrocarbon receptor (AhR). The present report is a systematic study of solid‐state forms of cardiosulfa and its biologically active analogues that belong to the N‐(9‐ethyl‐9H‐carbazol‐3‐yl)benzene sulfonamide skeleton. Cardiosulfa (molecule 1 ; R1=NO2, R2=H, R3=CF3), molecule 2 (H, H, CF3), molecule 3 (CF3, H, H), molecule 4 (NO2, H, H), molecule 5 (H, CF3, H), and molecule 6 (H, H, H) were synthesized and subjected to a polymorph search and solid‐state form characterization by X‐ray diffraction, differential scanning calorimetry (DSC), variable‐temperature powder X‐ray diffraction (VT‐PXRD), FTIR, and solid‐state (ss) NMR spectroscopy. Molecule 1 was obtained in a single‐crystalline modification that is sustained by N? H???π and C? H???O interactions but devoid of strong intermolecular N? H???O hydrogen bonds. Molecule 2 displayed a N? H???O catemer C(4) chain in form I, whereas a second polymorph was characterized by PXRD. The dimorphs of molecule 3 contain N? H???π and C? H???O interactions but no N? H???O bonds. Molecule 4 is trimorphic with N? H???O catemer in form I, and N? H???π and C? H???O interactions in form II, and a third polymorph was characterized by PXRD. Both polymorphs of molecule 5 contain the N? H???O catemer C(4) chain, whereas the sulfonamide N? H???O dimer synthon R22(8) was observed in polymorphs of 6 . Differences in the strong and weak hydrogen‐bond motifs were correlated with the substituent groups, and the solubility and dissolution rates were correlated with the conformation in the crystal structure of 1 , 2 , 3 , 4 , 5 , 6 . Higher solubility compounds, such as 2 (10.5 mg mL?1) and 5 (4.4 mg mL?1), adopt a twisted confirmation, whereas less‐soluble 1 (0.9 mg mL?1) is nearly planar. This study provides practical guides for functional‐group modification of drug lead compounds for solubility optimization.  相似文献   

17.
Reductive coupling reaction of aryliminomethylferrocenes FcCH = NAr[(1, Ar=QHs (a), p‐ClC6H4 (b), p‐BrC6H4 (c), p‐CH3C6H4 (d), m‐ClC6H4 (e)] with triethyl orthoformate (2) in Zn‐TiCl4 system gave three kinds of products: 1, 3‐diaryl‐4, 5‐diferrocenyl imidazolidines (3), N, N‐disubstituted formamides (4), and 1, 2‐diferrocenyl ethylene (5). 1H NMR spectra proved that all the compounds 3 obtained were dl‐isomers. All the new compounds 3 and 4 were characterized by elemental analysis, 1H NMR, 13C NMR (for 3) and IR spectra. The molecular structure of 3c was determined by X‐ray diffraction.  相似文献   

18.
Treatment of the metal reagent IrCl3 ? nH2O with two equivalents of 2‐pyridyl pyrazole (N^N)H (3‐tert‐butyl‐5‐(2‐pyridyl) pyrazole, (bppz)H and 3‐trifluoromethyl‐5‐(2‐pyridyl) pyrazole, (fppz)H), afforded the isomeric IrIII metal complexes with a general formula cis‐[Ir(bppz)2Cl2]H ( 2 a ), trans‐[Ir(bppz)2Cl2]H ( 3 a ), cis‐[Ir(fppz)2Cl2]H ( 2 b ), and trans‐[Ir(fppz)2Cl2]H ( 3 b ). Single‐crystal X‐ray diffraction studies on 2 b and 3 a revealed the coexistence of two pyrazolate chelates and two terminal chloride ligands on the coordination sphere. Subsequent reactivity studies confirmed their intermediacy to the preparation of homoleptic mer‐[Ir(bppz)3] ( 1 a ) and mer‐[Ir(fppz)3] ( 1 b ) that showed dual intraligand and ligand‐to‐ligand charge‐transfer phosphorescence at room temperature. To attain bright, room‐temperature phosphorescence further, we then synthesized two isoquinolinyl pyrazolate complexes, mer‐[Ir(bipz)3] ( 4 a ) and mer‐[Ir(fipz)3] ( 4 b ) ((bipz)H=3‐tert‐butyl‐5‐(1‐isoquinolyl) pyrazole and (fipz)H=3‐trifluoromethyl‐5‐(1‐isoquinolyl) pyrazole). Their orange luminescence is mainly attributed to the mixed MLCT/ππ* transition, and the quantum yields were as high as 86 ( 4 a ) and 50 % ( 4 b ) in degassed CH2Cl2 solution at RT. The organic light‐emitting diodes (OLEDs) were then fabricated by using 4 a as a dopant, giving orange luminescence with CIEx,y=0.55, 0.45 (CIEx,y=the 1931 Commission Internationale de L’Eclairage (x,y) coordinates) and peak efficiencies of 14.6 % photon/electron, 34.8 cd A?1, 26.1 lm W?1. The device data were then compared with the previously reported heteroleptic complex [Ir(dfpz)2(bipz)] ( 5 ) ((dfpz)H=1‐(2,4‐difluorophenyl) pyrazole), revealing the possible effect of the bipz chelate and phosphor design on the overall electrophosphorescent performance, which can be understood by the differences in the carrier‐transport properties.  相似文献   

19.
The reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde and N‐benzylmethylamine under microwave irradiation gives 5‐[benzyl(methyl)amino]‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde, C19H19N3O, (I). Subsequent reactions under basic conditions, between (I) and a range of acetophenones, yield the corresponding chalcones. These undergo cyclocondensation reactions with hydrazine to produce reduced bipyrazoles which can be N‐formylated with formic acid or N‐acetylated with acetic anhydride. The structures of (I) and of representative examples from this reaction sequence are reported, namely the chalcone (E )‐3‐{5‐[benzyl(methyl)amino]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl}‐1‐(4‐bromophenyl)prop‐2‐en‐1‐one, C27H24BrN3O, (II), the N‐formyl derivative (3RS )‐5′‐[benzyl(methyl)amino]‐3′‐methyl‐1′,5‐diphenyl‐3,4‐dihydro‐1′H ,2H‐[3,4′‐bipyrazole]‐2‐carbaldehyde, C28H27N5O, (III), and the N‐acetyl derivative (3RS )‐2‐acetyl‐5′‐[benzyl(methyl)amino]‐5‐(4‐methoxyphenyl)‐3′‐methyl‐1′‐phenyl‐3,4‐dihydro‐1′H ,2H‐[3,4′‐bipyrazole], which crystallizes as the ethanol 0.945‐solvate, C30H31N5O2·0.945C2H6O, (IV). There is significant delocalization of charge from the benzyl(methyl)amino substituent onto the carbonyl group in (I), but not in (II). In each of (III) and (IV), the reduced pyrazole ring is modestly puckered into an envelope conformation. The molecules of (I) are linked by a combination of C—H…N and C—H…π(arene) hydrogen bonds to form a simple chain of rings; those of (III) are linked by a combination of C—H…O and C—H…N hydrogen bonds to form sheets of R 22(8) and R 66(42) rings, and those of (IV) are linked by a combination of O—H…N and C—H…O hydrogen bonds to form a ribbon of edge‐fused R 24(16) and R 44(24) rings.  相似文献   

20.
Six novel palladium(II) complexes of a thiosemicarbazone Schiff base with isatin moiety (PdL1 to PdL6) were synthesized by the reaction of palladium(II) with the following: (Z )‐2‐(2‐oxoindolin‐3‐ylidene)‐N ‐phenylhydrazinecarbothioamide (L1H), (Z )‐2‐(5‐methyl‐2‐oxoindolin‐3‐ylidene)‐N ‐phenylhydrazinecarbothioamide (L2H), (Z )‐2‐(5‐fluoro‐2‐oxoindolin‐3‐ylidene)‐N ‐phenylhydrazinecarbothioamide (L3H), (Z )‐N ‐methyl‐2‐(5‐nitro‐2‐oxoindolin‐3‐ylidene)hydrazinecarbothioamide (L4H), (Z )‐N ‐methyl‐2‐(5‐methyl‐2‐oxoindolin‐3‐ylidene)hydrazinecarbothioamide (L5H) and (Z )‐N ‐ethyl‐2‐(5‐methyl‐2‐oxoindolin‐3‐ylidene)hydrazinecarbothioamide (L6H). The structures of these complexes were characterized using elemental analysis and infrared, UV–visible, 1H NMR and mass spectroscopies. The structure of PdL5 was further characterized using single‐crystal X‐ray diffraction. The interaction of these complexes with calf thymus DNA was characterized with a high intrinsic binding constant (K b = 5.78 × 104 to 1.79 × 106 M−1), which reflected the intercalative activity of these complexes towards calf thymus DNA. This result was also confirmed from viscosity data. Electrophoresis studies revealed that complexes PdL1 to PdL6 could cleave DNA via an oxidative pathway in the presence of an external agent. Data obtained from an in vitro anti‐proliferative study clearly established the anticancer potency of these compounds against the human colorectal carcinoma cell line HCT 116.  相似文献   

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