Volume 67, Issue 5

Two new Daphniphyllum alkaloids, daphhimalenines C and D (1and 2) were isolated from the leaves of Daphniphyllum himalense. Their structures were established by spectroscopic methods, especially 2D NMR techniques. Graphical Abstract Daphhimalenines C and D. New Alkaloids from Daphniphyllum himalense

The pyrrolizidine alkaloid intermedine-N-oxide was isolated from Cerinthe glabra for the first time. Due to the questionable assignments of NMR signals of this compound in previous literature reports ab initio calculations of the 13 C NMR values based on the GIAO approach, using HF and B3LYP levels of theory and the four basis sets 6-31G(d), 6-311G(d), 6-31G(d,p), and 6-311G(d,p) were performed. The assignments obtained this way are in very good accordance with the experimental values. Graphical Abstract Isolation of the Pyrrolizidine Alkaloid Intermedine-N-oxide from Cerinthe glabra and ab initio Calculation of its 13 C NMR Shifts

A new thiazolyl-indole alkaloid, barakacin (1), has been isolated from the ruminal bacterium Pseudomonas aeruginosa strain ZIO. On the basis of detailed spectroscopic analyses and comparison with the data of related compounds, its structure has been determined as 2-{4-[bis-(1H-indol-3- yl)-methyl]-thiazol-2-yl}-phenol. In addition, the known compounds phenazine-1-carboxylic acid, 3-(hydroxyacetyl)-indole, indole-3-carbaldehyde, and glycolipid A were isolated. The discovery of compounds with a new skeleton emphasizes the importance for exploring new ecological niches like the rumen of bovines for the detection of new natural products. This paper describes the fermentation, isolation, structure elucidation and biological activities of compound 1. Graphical Abstract Barakacin: A Thiazolyl-indole Alkaloid Isolated from a Ruminal Pseudomonas sp.

Phytochemical investigation of the whole plant of Achillea millefolium led to the isolation of three new sesquiterpenes which were trivially named as sesquiterpene lactone-esters A and B (1 and 2), and sesquiterpene lactone-diol (3). The structures of these compounds were determined with the help of one- and two-dimensional (1D and 2D) NMR techniques including 1 H NMR, 13 C NMR, HMQC, HMBC, COSY, and NOESY experiments. Graphical Abstract Isolation and Structure Determination of Three New Sesquiterpenoids from Achillea millefolium

Atalantia retusa Merr. is a rare Philippine endemic shrub which was reported to exhibit high antinociceptive and anti-inflammatory activities. The dichloromethane extract of the air-dried leaves of A. retusa afforded a new triterpene, retusenol (1), and friedelin (2), dischidiol (3), 5,7-dimethoxy-8- (3-methyl-2-oxybutyl)coumarin (4), humulene (5), and β-caryophyllene (6). The structures of 1 - 4 were elucidated by extensive 1D and 2D NMR experiments. Friedelin, a known analgesic and antiinflammatory drug, is an active principle of the shrub. Compounds 1 - 4 were tested for cytotoxicity against the human cancer lung adenocarcinoma A549, colon carcinoma HCT116 and the non-cancer Chinese hamster ovary AA8 using the MTT assay. Triterpenes 1 - 3 had no linear interpolation with HCT 116 and A549, thus the IC 50 value could not be computed. This implied that these compounds did not exhibit any cytotoxic effect against these cell lines. Meanwhile, 4 exhibited moderate cytoxicity against A549, HCT 116 and AA8 with IC 50 values of 47.5634, 42.4338 and 46:2751 μ g mL -1 , respectively. Compounds 1, 2 and 4 were tested for their antimicrobial properties against seven microorganisms and exhibited the highest activity against B. subtilis, even surpassing the activity of the standard antibiotic Chloramphenicol. They also exhibited antimicrobial activities against P. aeruginosa, S. aureus, C. albicans, and T. mentagrophytes, but were inactive against A. niger and E. coli. Graphical Abstract A New Triterpene from Atalantia retusa Merr.

Pakistamides A and B (1and 2, respectively), two new sphingolipids, have been isolated from the AcOEt-soluble sub-fraction of the MeOH extract of the whole plant of Abutilon pakistanicum. Their structures were assigned by 1 H and 13 C NMR spectra, and by DEPT and COSY, NOESY, HMQC, HMBC, EI-MS, and FAB-MS experiments. Graphical Abstract New Sphingolipids from Abutilon pakistanicum

Ten 1,10-secoguaianolides were isolated from the flowers of Achillea millefolium. Their structures were determined on the basis of spectroscopic methods. Three of them (millifolides A-C) including two dimeric sesquiterpenoids exhibit new skeletons. Seco-tanapartholide A exhibited moderate cell growth inhibitory activity against the human cancer cell line MCF7WT (IC 50 = 5.51 μm) in vitro. Graphical Abstract Millifolides A–C. New 1,10-Seco-guaianolides from the Flowers of Achillea millefolium

The reaction of 1,4-diaminobutane with hydroiodic acid in the presence of iodine yields the title compound 1,4-diazaniumbutane tetraiodide, C 4 H 14 N 2 I 4 (1). The title compound has been structurally characterized by crystallographic and spectroscopic methods (Raman and IR). 1is built up by centrosymmetric 1,4-diazaniumbutane cations in all-trans conformation and linear I4 2- anions. Both, cations and anions are located on centers of inversion (2/m) in the monoclinic space group C2/m. The hydrogen bonds between the azanium groups and the terminal iodine atoms of the I4 2- anions lead to a three-dimensional framework. The structural parameters of the tetraiodide anion, derived from X-ray crystallographic data are in excellent agreement with the results from Raman spectroscopy. The Raman and IR data for the analogous a,w-diazaniumalkane tetraiodide salts (H 3 N - (CH 2 ) 6 -NH 3 )I 4 (2) and (H 3 N-(CH 2 ) 7 -NH 3 )I 4 (3) are reported, and the structures of 1, 2and 3are compared. Graphical Abstract Synthesis, Structure and Spectroscopy of a New Polyiodide in the α,ω-Diazaniumalkane Iodide/Iodine System

The reaction between 2-(2-amino-ethylamino)ethanol and pyridine-2-carbaldehyde in a 1 : 3 molar ratio gave 3-(pyridin-2-yl)-1-(pyridin-2-ylmethyl)imidazo[1,5-a]pyridine (PPIP) which was characterized by elemental analysis and spectroscopic methods. The study of CSD-deposited structures revealed that PPIP is a new derivative of imidazo[1,5-a]pyridine. The cadmium chloride complex of this ligand [Cd(PPIP)Cl 2 ][Cd(PPIP)Cl 2 ]ʹ·3H 2 O (1) was prepared and identified by elemental analysis, FT-IR, Raman and 1 H NMR spectroscopy, and single-crystal X-ray diffraction. In the crystal structure of 1, there are two cadmium complexes with slightly different coordination bond lengths and angles. Also water molecules are incorporated in the crystal network. The geometry around the cadmium atom which is coordinated by two pyridine and one imine nitrogen atoms and two chloride ions is distorted square pyramidal. All bond lengths compare well with CSD averages of similar structures. The hydrogen bonds including O-H...Cl and O-H...O present in the crystal structure of 1 are also comparable to those in analogs. Graphical Abstract Synthesis, Crystallographic and Spectral Characterization of a Cadmium Chloride Complex Containing a Novel Imidazo[1,5-a]Pyridine Derivative

Two new coordination polymers constructed with the 1,10-phenanthroline derivative 2-(2-chloro- 6-fluorophenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline (L) and different carboxylates, namely, [Cd 2 (L) 2 (1,3,5-BTC)(Cl)]·H 2 O (1) and [Co 2 (L) 2 (1,2,4,5-BTC)(H 2 O) 2 ] (2), have been synthesized under hydrothermal conditions (1,3,5-BTC = 1,3,5-benzenetricarboxylate anion and 1,2,4,5-BTC = 1,2,4,5-benzenetetracarboxylate anion). Crystal data for 1: C 47 H 25 Cd 2 Cl 3 F 2 N 8 O 7 , triclinic, space group P¯1, a = 10:1084(5), b = 14:9285(7), c = 15:2930(4)Å , α = 72:1050(10), β = 86:160(2), γ = 79:6000(10)°, V = 2159:88(16) °A 3 , Z = 2. Crystal data for 2: C 24 H 13 ClCoFN 4 O 5 , triclinic, space group P1¯, a = 7:4767(15), b = 10:094(2), c = 14:772(3)Å , α = 91:23(3), β = 100:95(3), γ = 106:57(3)°, V = 1045:8(4) Å 3 , Z = 2. Their crystal structures have been determined by singlecrystal X-ray diffraction analyses, and the compounds further characterized by physico-chemical and spectroscopic methods. In 1, each 1,3,5-BTC anion connects five Cd(II) atoms to form a double chain. These chains are extended into 2D supramolecular networks through μ - μ interactions. N-H...Cl, N - H...O and O - H...N hydrogen bonding interactions further stabilize the network of 1. In 2, each 1,2,4,5-BTC anion bridges four Co(II) atoms to yield a chain. μ-μ interactions among adjacent chains result in a 2D supramolecular architecture. Graphical Abstract Two New Cd(II) and Co(II) Coordination Polymers Based on a 1,10- Phenanthroline Derivative and Tri- or Tetra-Carboxylates: Syntheses, Structures and Photoluminesce

Three new mixed-ligand complexes of silver(I) with 4,4ʹ-bipyridine and derivates of benzoyltrifluoroacetone (Htfpb: 4,4,4-trifluoro-1-phenyl-1,3-butandione, Htfcpb: 4,4,4-trifluoro-1-(4- chlorophenyl)-1,3-butandione and Htfmpb: 4,4,4-trifluoro-1-(4-methoxyphenyl)-1,3-butandione) were synthesized and characterized by elemental analyses and 1 H NMR spectroscopy. Thermal and electrochemical properties were also studied. The single-crystal structure of [Ag(4,4ʹ-bpy)(tfcpb)] n shows a one-dimensional coordination polymer as a result of 4,4ʹ-bpy bridging. The four-coordinate Ag(I) ions are linked into double chains by Ag...O contacts, which are extended into a 3D supramolecular structure through abundant weak interactions, such as μ...μ, C-H...F, C-H...O, C-H...Cl and F...F contacts. Graphical Abstract Synthesis and Spectroscopic, Thermal and Electrochemical Studies of Mixed-ligand Complexes of Silver(I) with Derivatives of Benzoyltrifluoroacetonate and 4,4ʹ-Bipyridine, Including the Crystal Structure of [Ag(4,4ʹ-bpy)(tfcpb)] n

The ternary stannide CeRuSn is a static mixed-valent cerium compound with an ordering of trivalent and intermediate-valent cerium on two distinct crystallographic sites. 119 Sn Mössbauer spectra showed two electronically almost identical tin atoms at 323 K, while at 298 K and below (77 and 4:2 K) two tin sites can clearly be distinguished. Solid-state 119 Sn NMR experiments were performed to probe the local hyperfine fields at the two different Sn sites. Powder 119 Sn NMR spectra are nicely fitted with two Sn sites with nearly the same magnetic anisotropy, but with different absolute shift values. Both Sn sites are strongly affected by crossover-like transitions between 100 and 280 K. This local-site study confirms the superstructure modulations found in previous investigations. Towards lower temperatures the powder NMR spectra are broadened giving strong precursor evidence for the antiferromagnetically ordered ground state. Graphical Abstract Solid-state 119 Sn NMR and M¨ossbauer Spectroscopic Studies of the Intermediate-valent Stannide CeRuSn

Three microbial polysaccharides, namely welan gum, scleroglucan, and EPS I, a novel polysaccharide obtained from a newly isolated bacillus species with structural similarities to xanthan gum, were employed in the fabrication of bio-nanocomposites based on layered double hydroxides (LDH). Synthesis was performed by direct co-precipitation of Zn(NO 3 ) 2 and Al(NO 3 ) 3 in the polysaccharide solutions at pH ~ 8.5. The reaction products were characterized by powder X-ray diffraction (XRD), elemental and thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning and transmission electron microscopy (SEM and TEM). It was found that welan gum is successfully intercalated into the Zn-Al-LDH structure, giving a d-spacing of 2:38 nm for the interlayer distance, while neutral scleroglucan failed to be intercalated. Instead, this biopolymer was only surface-adsorbed on inorganic CaAl-OH-LDH platelets, as was evidenced by de-washing experiments. These results indicate that the anionic functionality of the polysaccharides presents a main driving force behind their intercalation. In contrast to regular xanthan gum, EPS I was intercalated into the LDH structure to give a sharp X-ray reflection representing a d-spacing of 2:77 nm. This behavior proves that slight modifications of the polysaccharide can greatly improve its intercalation ability. Graphical Abstract Intercalation of the Microbial Biopolymers Welan Gum and EPS I into Layered Double Hydroxides

In the absence of oxygen the photolysis of [Os(NH 3 ) 5 (N 2 )] 2+ leads to the reduction of the N 2 ligand according to [Os II (NH 3 ) 5 (N 2 )] 2+ + H 2 O → [Os VI (NH 3 ) 4 N] 3+ + N 2 H 4 + OH - . The photochemical formation of hydrazine from N 2 is discussed with regard to the photochemical conversion and storage of solar energy. Graphical Abstract Photolysis of Aqueous [Os(NH 3 ) 5 (N 2 )] 2+ . Photoreduction of Coordinated Dinitrogen to Hydrazine as a Model for a New Type of Artificial Photosynthesis?

Sildenafil citrate monohydrate, well known as Viagra ® , is a drug for the treatment of erectile dysfunction. Here we present the X-ray crystal structure of the sildenafil base, C 22 H 30 N 6 O 4 S. The compound crystallizes in the monoclinic system, space group P2 1 /c with the unit cell parameters a = 17:273(1), b=17:0710(8), c=8:3171(4) Å , b =99:326(2), Z = 4, V = 2420:0(3) Å 3 . A comparison with the known crystal structures of sildenafil citrate monohydrate and sildenafil saccharinate is also presented. Graphical Abstract Molecular and Crystal Structure of Sildenafil Base

A sandwich-type tungstophosphate, (1,3-H 2 dap) 2 H 4 [Co 4 (1,3-Hdap) 2 (α-B-PW 9 O 34 ) 2 ] ·3H 2 O (1,3-dap=1,3-diaminopropane), was hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental and thermo-gravimetric analysis, and IR and UV spectroscopy. The compound presents a classical tetra-transition metal-substituted sandwich framework, [Co 4 (1,3-Hdap) 2 (α-B-PW 9 O 34 ) 2 ] 8- , which contains two lacunary α-B-[PW 9 O 34 ] 9- Keggin units linked by a rhomblike Co 4 O 14 (1,3-dap) 2 cluster lying across an inversion center. The Co 2+ ions are coordinated by a mono-protonated dap ligand. Isolatedly protonated 1,3-dap units act as counter-ions interacting with the [PW 9 O 34 ] 9- polyanions via hydrogen bonds forming a three-dimensional framework. Graphical Abstract Synthesis and Structural Characterization of a Tetra-Cobalt(II)-substituted Sandwich-type Tungstophosphate, (1,3-H 2 dap) 2 H 4 [Co 4 (1,3-Hdap) 2 (α-BPW 9 O 34 ) 2 ]·3H 2 O

A metal-organic framework based on 5-iodo-isophthalic acid (5-iipaH 2 ) and the ancillary nitrogen ligand 1,3-bi(4- pyridyl)propane (bpp), namely [Cd(5-iipa)(bpp)(H 2 O)] n (1), has been synthesized, and characterized by IR spectroscopy, elemental analysis, thermogravimetry, and X-ray crystallography. Complex 1shows a two-fold interpenetrating 3D diamond-like architecture that is stabilized by hydrogen bonding, μ...μ, I...μ, and C-H...p interactions. Graphical Abstract A Two-fold Interpenetrated Diamondlike 3D Metal-Organic Cd(II) Complex Based on 5-Iodo-isophthalic Acid and 1,3-Bi(4-pyridyl)propane

The synthesis and structural characterization of the Nsubstituted bis(diphenylphosphanyl)amine Ph 2 PN(R)PPh 2 (R = n-propyl, 1) is reported. Single crystals of 1grown from dichloromethane/acetonitrile have been analyzed by Xray crystallography. The crystallographic study revealed that the diphenylphosphanyl groups in 1are staggered relative to the PNP backbone as observed for other closely related molecules. Graphical Abstract Structural Characterization of N,NBis( diphenylphosphanyl)propylamine