Accessing bimetallic complexes through a variable bridging ligand strategy.

In this contribution we are introducing a Variable Bridging Ligand (VBL) strategy for the preparation of heterometallic complexes. One synthetic challenge associated with other methods described in the existing literature stems from the fact that if there is a need to change the donor groups on a metalloligand, both the initial ligand and the resulting metalloligand must be synthesized all over again. To circumvent this problem, we reasoned that if a metal complex would have one labile ligand that can be easily replaced by various bridging polytopic species, several metalloligands can thus be generated starting from the same starting material.

Benzoyl Valine Quasiracemates: Pairing CF Quasienantiomers with H to -Butyl.

Understanding the interplay of structural features responsible for molecular assembly is essential for molecular crystal engineering. When assembling molecules with encoded motifs, supramolecular strategies almost always include robust directional nonbonded contacts. Quasiracemic materials, considered near racemates since cocrystallization occurs with chemically unique components, lack a molecular framework or functional group restrictions, highlighting the importance of molecular shape to molecular assembly.

Synthesis, Structure and Anticancer Activity of a Dinuclear Organoplatinum(IV) Complex Stabilized by Adenine.

The dinuclear organoplatinum(IV) compound {Pt(CH)}(μ-I)(μ-adenine) (abbreviated ), obtained by treating cubic [Pt(CH)(μ-I)] with two equivalents of adenine, was isolated and structurally characterized by single crystal X-ray diffraction. The National Cancer Institute Developmental Therapeutics Program's sulforhodamine B assays showed to be particularly cytotoxic against central nervous system cancer cell line SF-539, and human renal carcinoma cell line RXF-393. Furthermore, displayed some degree of cytotoxicity against non-small cell lung cancer (NCI-H522), colon cancer (HCC-2998, HCT-116, HT29, and SW-620), melanoma (LOX-IMVI, MALME-3M, M14, MDA-MB-435, SK-MEL-28, and UACC-62), ovarian cancer (OVCAR-5), renal carcinoma (A498), breast cancer (BT-549 and MDA-MB-468), and triple-negative breast cancer (MDA-MB-231).

Dual space divergence in small molecule quasiracemates: benzoyl leucine and phenylalanine assemblies.

Quasiracemic materials constructed with two points of structural difference were used to understand the role molecular shape plays in molecular assembly. Hot stage, crystallographic and occupied cavity space assessments provide insight into how imposed CH/Cl and H/CF structural variations placed on benzoyl leucine and phenylalanine scaffolds result in a remarkably high occurrence of cocrystal formation.

Crystal structure and Hirshfeld surface analysis of tri-aza-triborinotris[1,3,2]benzodi-aza-borole acetone disolvate.

The title compound, alternatively known as benzodi-aza-borole trimer, CHBN·2CHO, at 100 K crystallizes in the triclinic system, space group . The structure displays N-H⋯O hydrogen bonding connecting the main mol-ecule with the crystallization solvent. Disorder of the main mol-ecule is observed with occupancy factors refined to 0.

Neutrophil-Mediated Delivery of Nanocrystal Drugs via Photoinduced Inflammation Enhances Cancer Therapy.

The efficient delivery of anticancer agents into tumor microenvironments is critical for the success of cancer therapies, but it is a prerequisite that drug carriers should overcome tumor vasculature and possess high drug contents. Here, we found that photoinduced inflammation response caused the migration of neutrophils into tumor microenvironments and neutrophils transported neutrophil-targeted nanoparticles (NPs) across the tumor blood barrier. The results showed that tumor delivery efficiencies of NPs were 5% ID/g, and they were independent of particle sizes (30-200 nm) and their doses (10-10 NPs).

Synthesis and Determination of Anticancer Activity of Dicobalt Hexacarbonyl 2'-Deoxy-5-alkynylfuropyrimidines.

Dicobalt hexacarbonyl 5-alkynyl furopyrimidine nucleoside analogs, with 4-methylphenyl (-tolyl) and 4-pentylphenyl substituents attached at the C-6 base position, designed in the form of ribose acetyl esters, were synthesized (42-96%). Attached at the C-5 position were propargyl alcohol, its methyl ether and acetate derivatives, butynol, and the 4-methylphenyl- (-tolyl) and 4-pentylphenyl-substituted alkynyl groups, which were coordinated to a dicobalt hexacarbonyl unit. The structure of 5-(3-acetoxyprop-1-yn-1-yl)-6--tolyl-2'-deoxyribofuranosyl-furo[2,3-]pyrimidin-2-one was determined by X-ray crystallography.

Crystal structures, Hirshfeld analysis, and energy framework analysis of two differently 3'-substituted 4-methylchalcones: 3'-(N=CHCH-p-CH)-4-methylchalcone and 3'-(NHCOCH)-4-methylchalcone.

Two crystal structures of chalcones, or 1,3-diarylprop-2-en-1-ones, are presented; both contain a p-methyl substitution on the 3-Ring, but differ with respect to the m-substitution on the 1-Ring. Their systematic names are (2E)-3-(4-methylphenyl)-1-(3-{[(4-methylphenyl)methylidene]amino}phenyl)prop-2-en-1-one (CHNO) and N-{3-[(2E)-3-(4-methylphenyl)prop-2-enoyl]phenyl}acetamide (CHNO), which are abbreviated as 3'-(N=CHCH-p-CH)-4-methylchalcone and 3'-(NHCOCH)-4-methylchalcone, respectively. Both chalcones represent the first reported acetamide-substituted and imino-substituted chalcone crystal structures, adding to the robust library of chalcone structures within the Cambridge Structural Database.

Anticancer Activity of Nonpolar Pt(CH)I{} is Found to be Superior among Four Similar Organoplatinum(IV) Complexes.

The anticancer properties of well-defined molecules serve to bolster the field of metals in medicine. Such compounds, particularly those of platinum and their closely related structural analogs, continue to be potentially highly interesting to researchers and clinicians alike. The four octahedral organoplatinum(IV) compounds [Pt(CH)X{ }] (X = Br, I; = 2,2'-bipyridine, 2,2'-bipyridine-4,4'-dicarboxylic acid) have been isolated and structurally characterized by single-crystal X-ray diffraction.

Synthesis, crystal structure and Hirshfeld analysis of triphenylphosphine-(4-bromophenyl)borane.

The title compound, alternatively called (4-bromophenyl)dihydrido(triphenylphosphanyl)boron, CHBBrP, crystallizes in the space group P-1 with one symmetry-independent molecule in the asymmetric unit. The B and P atoms both adopt the expected tetrahedral geometry. A possible intramolecular B-H.

Recent Advances in the Synthesis of Isoquinoline-Fused Benzimidazoles.

This review includes recent developments in the synthesis of benzo[4,5]imidazo[2,1-]isoquinolines with particular attention given to categorizing protocols based on the structural features of the ring architecture and crystallographically characterized reaction products.

Asymmetric Synthesis of Bicyclic Pyrazolidinones through Alkaloid-Catalyzed [3+2]-Cycloadditions of Ketenes and Azomethine Imines.

A versatile asymmetric synthesis of bicyclic pyrazolidinones through alkaloid-catalyzed formal [3+2]- and [3+2+2]-cycloadditions of ketenes with azomethine imines is described. The methodology was found to be tolerant of ketene and a variety of monosubstituted ketenes (R=alkyl, OAc). The products were formed in good to excellent yields (71-99 % for 24 examples, 39 examples in all), with good to excellent diastereoselectivity in many cases (dr 3 : 1 to 27 : 1 for 22 examples), and with excellent enantioselectivity for most examples (≥93 % ee for 34 products).

Extension of furopyrimidine nucleosides with 5-alkynyl substituent: Synthesis, high fluorescence, and antiviral effect in the absence of free ribose hydroxyl groups.

A novel methodology to access alkynyl nucleoside analogues is elaborated. Highly fluorescent 5-alkynylfuropyrimidines were synthesized (97-46%) and their antiviral properties investigated in vitro. Regiochemistry of the functionalization was achieved with the aid of 5-endo-dig electrophilic halocyclization of acetyl 5-p-tolyl- or 5-p-pentylphenyl-2'-deoxyuridine.

P-stereocontrolled synthesis of oligo(nucleoside N3'→O5' phosphoramidothioate)s - opportunities and limitations.

3'--(2-Thio-1,3,2-oxathiaphospholane) derivatives of 5'--DMT-3'-amino-2',3'-dideoxy-ribonucleosides (OTP-N), that bear a 4,4-unsubstituted, 4,4-dimethyl, or 4,4-pentamethylene substituted oxathiaphospholane ring, were synthesized. Within these three series, OTP-N differed by canonical nucleobases (, Ade, Cyt, Gua, or Thy). The monomers were chromatographically separated into P-diastereomers, which were further used to prepare NN' dinucleotides (3), as well as short P-stereodefined oligo(deoxyribonucleoside N3'→O5' phosphoramidothioate)s (NPS-) and chimeric NPS/PO- and NPS/PS-oligomers.

Crystal structure and Hirshfeld analysis of 3'-bromo-4-methyl-chalcone and 3'-cyano-4-methyl-chalcone.

Two crystal structures of chalcones, or 1,3-di-aryl-prop-2-en-1-ones, are presented; both contain a methyl substitution on the 3-Ring, but differ on the 1-Ring, bromo cyano. The compounds are 3'-bromo-4-methyl-chalcone [systematic name: 1-(2-bromo-phen-yl)-3-(4-methyl-phen-yl)prop-2-en-1-one], CHBrO, and 3'-cyano-4-methyl-chalcone {systematic name: 2-[3-(4-methyl-phen-yl)prop-2-eno-yl]benzo-nitrile}, CHNO. Both chalcones meaningfully add to the large dataset of chalcone structures.

Benzobis(imidazolium) salts as templates for the self-assembly of starburst [2]pseudorotaxanes and their corresponding carbene-based classic [2]pseudorotaxanes.

Benzobis(imidazolium) salts ([BBI-H2-R4]2+, R = alkyl, aryl) interact with crown ethers through a combination of hydrogen bonds, ion-dipole, and π-π stacking interactions to form starburst [24]pseudo-rotaxanes. This new recognition motif allows the extension of four side-arms directly from the cavity of the crown ether, thus positioning the wheel component in a straddled orientation onto the axle, while their carbene-based derivatives show the classical shape of regular [22]pseudorotaxanes.

Multiple coordination modes of a new ditopic bis(pyrazolyl)methane-based ligand.

A new ditopic ligand, N-(2,2-bis(pyrazolyl)ethyl)-2,2-bis(pyrazolyl)acetamide ((pz)CH-C(O)-NH-CH-CH(pz), L4Pz, pz = pyrazolyl ring), comprising two bis(pyrazolyl)methane donor groups linked via an amide bridge, has been prepared from the reaction of HOOCCH(pz) and HNCHCH(pz). The ligand coordinates to various metallic salts (i.e.

Organometallic Nucleosides: Synthesis and Biological Evaluation of Substituted Dicobalt Hexacarbonyl 2'-Deoxy-5-oxopropynyluridines.

Reactions of dicobalt octacarbonyl [Co(CO)] with 2'-deoxy-5-oxopropynyluridines and related compounds gave dicobalt hexacarbonyl nucleoside complexes (83-31 %). The synthetic outcomes were confirmed by X-ray structure determination of dicobalt hexacarbonyl 2'-deoxy-5-(4-hydroxybut-1-yn-1-yl)uridine, which exhibits intermolecular hydrogen bonding between a modified base and ribose. The electronic structure of this compound was characterized by the DFT calculations.

Correction: Sisters together: co-sensitization of near-infrared emission of ytterbium(iii) by BODIPY and porphyrin dyes.

Correction for 'Sisters together: co-sensitization of near-infrared emission of ytterbium(iii) by BODIPY and porphyrin dyes' by Hongshan He et al., Chem. Commun.

Sisters together: co-sensitization of near-infrared emission of ytterbium(iii) by BODIPY and porphyrin dyes.

A ytterbium(iii) acetate complex with a BODIPY and a porphyrin as co-sensitizers emits strongly at 978 nm over a broader excitation window between 450-560 nm.

Multicomponent reaction through cooperative trio catalysis incorporating enamine, Brønsted acid and metal Lewis acid catalysis: a concise route to access chromans.

An atom-economical multicomponent cascade reaction of salicylaldehydes, cyclohexanones and arylamines has been developed for the synthesis of three-ring fused chromans. This reaction was achieved through cooperative enamine-metal Lewis acid assisted Brønsted acid catalysis, furnishing the products in excellent yields with good diastereoselectivity.

Mapping the structural boundaries of quasiracemate fractional crystallization using 2-substituted diarylamides.

Video-assisted hot stage polarized light microscopy of 55 quasienantiomeric pairs, constructed from 22 chiral diarylamides that systematically differ in topology, reveals the structural boundaries of molecular shape to supramolecular assembly.

Monitoring a simple hydrolysis process in an organic solid by observing methyl group rotation.

We report a variety of experiments and calculations and their interpretations regarding methyl group (CH) rotation in samples of pure 3-methylglutaric anhydride (1), pure 3-methylglutaric acid (2), and samples where the anhydride is slowly absorbing water from the air and converting to the acid [CHO(1) + HO → CHO(2)]. The techniques are solid state H nuclear magnetic resonance (NMR) spin-lattice relaxation, single-crystal X-ray diffraction, electronic structure calculations in both isolated molecules and in clusters of molecules that mimic the crystal structure, field emission scanning electron microscopy, differential scanning calorimetry, and high resolution H NMR spectroscopy. The solid state H spin-lattice relaxation experiments allow us to observe the temperature dependence of the parameters that characterize methyl group rotation in both compounds and in mixtures of the two compounds.

Asymmetric Synthesis of γ-Lactones through Koga Amine-Controlled Addition of Enediolates to α,β-Unsaturated Sulfoxonium Salts.

A chiral Koga amine-controlled asymmetric synthesis of cis-γ-lactones through a formal [3 + 2] cycloaddition of enediolates with α,β-unsaturated sulfoxonium salts is described. The desired structural motif was formed in moderate to good yields (50-71% for 13 examples), with good to very good diastereoselectivity (dr 5:1 to 10:1 for 20 examples), favoring the cis-isomer, and good to excellent enantioselectivity (70-91% ee for 13 examples).

Crystal structure of (OC)W(μ-dppe)W(CO).

The centrosymmetric title complex, [μ-ethane-1,2-diylbis(di-phenyl-phosphane)-κ:']bis-[penta-carbonyl-tungsten(0)], [W(CHP)(CO)], consists of two W(CO) moieties bridged by a bis-(di-phenyl-phosphan-yl)ethane (dppe) ligand. The W atom has a slightly distorted octa-hedral coordination environment consisting of 5 carbonyl ligands and one P atom from the bridging dppe ligand with the nearest W atom 5.625 (5) Å away.