bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Palladium‐Catalyzed Direct Arylation of Heteroaromatic Compounds: Improved Conditions Utilizing Controlled Microwave Heating.
Authors: Baghbanzadeh Mostafa , Pilger Christian , Kappe C. Oliver 
Published: January 2012

AbstractA wide range of arylated heteroaryls and bisheteroaryls can be prepared in good to high yields.
ChemInform Abstract: Potassium tert‐Butoxide Mediated Heck‐Type Cyclization/Isomerization—Benzofurans from Organocatalytic Radical Cross‐Coupling Reactions.
Authors: Rueping Magnus , Leiendecker Matthias , Das Arindam , Poisson Thomas , Bui Lan 
Published: January 2012

AbstractA transition metal‐free Heck‐type cyclization/isomerization reaction mediated by KOtBu and phenanthroline is described.
ChemInform Abstract: Binaphthol‐Derived Bisphosphoric Acids Serve as Efficient Organocatalysts for Highly Enantioselective 1,3‐Dipolar Cycloaddition of Azomethine Ylides to Electron‐Deficient Olefins.
Authors: He Long , Chen Xiao‐Hua , Wang De‐Nan , Luo Shi‐Wei , Zhang Wen‐Quan , Yu Jie , Ren Lei , Gong Liu‐Zhu 
Published: January 2012

AbstractAmong several chiral bisphosphoric acids evaluated, oxygen‐linked acid BNO provides the highest level of stereoselectivity.
ChemInform Abstract: A Simple and Efficient Protocol to 1,2,4‐Substituted Pyrroles via a Sonogashira Coupling—Acid‐Catalyzed Cyclization.
Authors: Zhu Da , Zhao Jie , Wei Yuxiu , Zhou Hongwei 
Published: January 2012

AbstractCoupling of bromides (I) and (IV) with alkynes is followed by cyclization of the non‐isolable intermediate to give the desired substituted pyrrole structures.
ChemInform Abstract: Gold‐Catalyzed Cycloisomerizations of 1‐(2‐(Tosylamino)phenyl)prop‐2‐yn‐1‐ols to 1H‐Indole‐2‐carbaldehydes and (E)‐2‐(Iodomethylene)indolin‐3‐ols.
Authors: Kothandaraman Prasath , Mothe Srinivasa Reddy , Toh Sharon Si Min , Chan Philip Wai Hong 
Published: January 2012

AbstractThe Au‐catalyzed treatment of substrates (I), (IV), and (VII) with NIS at low temperature allows a simple and efficient access to (E)‐2‐(iodomethylene)indolinols.
ChemInform Abstract: Triphenylphosphine‐Catalyzed [3 + 2] Cycloaddition of Allenoate and Active Olefins: Synthesis of Spirooxindole Derivatives.
Authors: Guo Shanyan , Wang Rendong , Li Jian , Li Chunju , Deng Hongmei , Jia Xueshun 
Published: January 2012

AbstractThe process proceeds with complete regioselectivity and allows the application in medicinal chemistry.
ChemInform Abstract: Convenient Modification of the Leimgruber—Batcho Indole Synthesis: Reduction of 2‐Nitro‐β‐pyrrolidinostyrenes by the FeCl3‐Activated Carbon—N2H4·H2O System.
Authors: Taydakov I. V. , Dutova T. Ya. , Sidorenko E. N. , Krasnoselsky S. S. 
Published: January 2012

AbstractAn unusual catalytic system containing ferric chloride, activated carbon, and hydrazine is successfully applied for the reductive cyclization step in the Leimgruber—Batcho indole synthesis.
ChemInform Abstract: Probing the Difference Between BH3 Groove of Mcl‐1 and Bcl‐2 Protein: Implications for Dual Inhibitors Design.
Authors: Zhang Zhichao , Yang Hongna , Wu Guiye , Li Zhiqiang , Song Ting , Li Xiang qian 
Published: January 2012

AbstractA series of 8‐oxo‐acenaphthopyrrole‐9‐carbonitriles (IV) are designed and synthesized.
ChemInform Abstract: Application of Ullmann and Ullmann—Finkelstein Reactions for the Synthesis of N‐Aryl‐N‐(1H‐pyrazol‐3‐yl)acetamide or N‐(1‐Aryl‐1H‐pyrazol‐3‐yl)acetamide Derivatives and Pharmacological Evaluation.
Authors: Deprez‐Poulain Rebecca , Cousaert Nicolas , Toto Patrick , Willand Nicolas , Deprez Benoit 
Published: January 2012

AbstractThe target compounds (IV) and (XI), which are synthesized using the title reactions, are evaluated for their pharmacological properties.
ChemInform Abstract: Regioselective Multicomponent Synthesis of Fully Substituted Pyrazoles and Bispyrazoles Catalyzed by Zinc Triflate.
Authors: Safaei Shirin , Mohammadpoor‐Baltork Iraj , Khosropour Ahmad Reza , Moghadam Majid , Tangestaninejad Shahram , Mirkhani Valiollah 
Published: January 2012

AbstractThe optimized conditions A) or B) render possible the reaction of aldehydes, aryl hydrazines and ester (III) to give high yields of the target compounds.
ChemInform Abstract: Synthesis of Novel 1,2,5‐Trisubstituted Benzimidazoles as Potential Antitumor Agents.
Authors: Abonia Rodrigo , Cortes Edwar , Insuasty Braulio , Quiroga Jairo , Nogueras Manuel , Cobo Justo 
Published: January 2012

AbstractThe compounds (III) are screened for their cytotoxic activity against a range of cancer cell lines.
ChemInform Abstract: Ligand‐ and Solvent‐Free Iron‐Catalyzed Oxidative Alkynylation of Azoles with Terminal Alkynes.
Authors: Patil Sachin S. , Jadhav Rahul P. , Patil Sachin V. , Bobade Vivek D. 
Published: January 2012

AbstractThe process can be applied to aliphatic and (het)aromatic alkyne substrates.
ChemInform Abstract: Synthesis and Biological Evaluation of New 3,5‐Di(trifluoromethyl)‐1,2,4‐triazolesulfonylurea and Thiourea Derivatives as Antidiabetic and Antimicrobial Agents.
Authors: Faidallah Hassan M. , Khan Khalid A. , Asiri Abdullah M. 
Published: January 2012

AbstractSeveral series of title compounds are prepared starting from (I) and screened for their antidiabetic and antimicrobial activities.
ChemInform Abstract: Amino Acids as Building Blocks for the Synthesis of Substituted 1,2,4‐Triazoles.
Authors: Bibian Mathieu , Martinez Jean , Fehrentz Jean‐Alain 
Published: January 2012

AbstractSilver benzoate is shown to promote the synthesis of 1,2,4‐triazoles bearing up to three chiral amino acid derived groups in positions 3, 4, and 5 of the triazole ring.
ChemInform Abstract: Diastereoselective Tin‐Free Tandem Radical Additions to 3‐Formylchromones.
Authors: Zimmerman Jake R. , Manpadi Madhuri , Spatney Russell , Baker Aaron 
Published: January 2012

AbstractThe stereoselective method to prepare 2,3‐disubstituted chromone derivatives creates 3 stereocenters with good to high selectivity.
ChemInform Abstract: Synthetic Studies of Substituted Pyridine Aldehydes as Intermediates for the Synthesis of Toddaquinoline, Its Derivatives and Other Natural Products.
Authors: Serban Georgeta , Abe Hitoshi , Takeuchi Yasuo 
Published: January 2012

AbstractThe highly practical and efficient synthesis of the substituted pyridine aldehydes (IV) and (VII), without the use of very expensive or dangerous reagents, are realized via the presented bromination and the DMF‐formylation step of the pyridine ring.
ChemInform Abstract: Regioselective 1,6‐Conjugate Addition of Boronic Acids and Grignard Reagents to Dienylpyridines.
Authors: Roscales Silvia , Salado Irene G. , Csaky Aurelio G. 
Published: January 2012

AbstractThe use of FeCl2 as the catalyst yields mixtures of E/Z‐olefins except in the case of substrates (VI), where only the (Z) isomers are formed.
ChemInform Abstract: Enantioselective Synthesis of Dihydropyridinones via NHC‐Catalyzed Aza‐Claisen Reaction.
Authors: Wanner Benedikt , Mahatthananchai Jessada , Bode Jeffrey W. 
Published: January 2012

AbstractThe reaction of various enals with enamides in the presence of chiral NHC affords enantioenriched dihydropyridinones without any need of N‐protection.
ChemInform Abstract: Novel Quinolines Bearing a Biologically Active Trimethoxyphenyl Moiety as a New Class of Antitumor Agents.
Authors: Al‐Said Mansour S. , Bashandy Mahmound S. , Ghorab Mostafa M. 
Published: January 2012

AbstractCompounds (IIIe), (IIIf) and (IIIg) show higher antitumor activity when compared with doxorubicin as reference drug.
ChemInform Abstract: Catalytic Asymmetric Alkynylation of C1‐Substituted C,N‐Cyclic Azomethine Imines by CuI/Chiral Broensted Acid Co‐Catalyst.
Authors: Hashimoto Takuya , Omote Masato , Maruoka Keiji 
Published: January 2012

AbstractThe alkynylation is also applicable to the synthesis of chiral tetrahydroisoquinoline derivatives with a tetrasubstituted carbon center at the C1‐position.
ChemInform Abstract: Synthesis and Pharmacological Assessment of Diversely Substituted Pyrazolo[3,4‐b]quinoline, and Benzo[b]pyrazolo[4,3‐g][1,8]naphthyridine Derivatives.
Authors: Carreiras M. Carmo , et al. et al. 
Published: January 2012

AbstractDiversely substituted tacrine analogues are synthesized by Friedlaender‐type reactions of readily available o‐amino‐1‐methylpyrazoledicarbonitrile derivatives with cyclohexanone.
ChemInform Abstract: N3‐Alkylation During Formation of Quinazolin‐4‐ones from Condensation of Anthranilamides and Orthoamides.
Authors: Threadgill Michael D. , et al. et al. 
Published: January 2012

AbstractOrthoamides with less sterically demanding alkyl groups such as (II), (IV) or (VI) act as both electrophilic one‐carbon unit and direct alkylating agents at N3 of anthranilamides (I).
ChemInform Abstract: Combustion Derived Nanocrystalline‐ZrO2 and Its Catalytic Activity for Biginelli Condensation under Microwave Irradiation.
Authors: Bhojegowd Madhusudana Reddy M. , Siddaramanna Ashoka , Shiddappa Anandakumar B. , Thimmanna Chandrappa G. , Pasha Mohamed A. 
Published: January 2012

AbstractThe catalyst can be recycled without change in its activity.
ChemInform Abstract: Targeting the Human Malaria Parasite Plasmodium falciparum: In vitro Identification of a New Antiplasmodial Hit in 4‐Phenoxy‐2‐trichloromethylquinazoline Series.
Authors: Vanelle Patrice , et al. et al. 
Published: January 2012

AbstractA two‐step approach yields quinazolines (IV), possessing a substituted phenoxy group at position 4.
ChemInform Abstract: The Preparation of 2H‐1,4‐benzoxazin‐3‐(4H)‐ones via Palladium‐Catalyzed Intramolecular C—O Bond Formation.
Authors: Ylijoki Kai E. O. , Kuendig E. Peter 
Published: January 2012

AbstractAryl‐ and alkyl‐substituted benzoxazinones are prepared via Pd‐catalyzed intramolecular C—O bond formation.
ChemInform Abstract: L‐Proline‐Catalyzed Three‐Component Domino Reactions for the Diastereoselective Synthesis of 5,6‐Disubstituted 3‐Thiomorpholinones.
Authors: Indumathi Sethuraman , Perumal Subbu , Menendez J. Carlos 
Published: January 2012

AbstractThe biologically important heterocyclic skeleton is formed with complete diastereoselectivity but in a nearly racemic form despite the presence of an optically active catalyst.
ChemInform Abstract: Stereoselective Synthesis of Functionalized Pyroglutamates.
Authors: Just Matthew J. , Tekkam Srinivas , Alam Mohammad A. , Jonnalagadda Subash C. , Johnson Joseph L. , Mereddy Venkatram R. 
Published: January 2012

AbstractA highly diastereoselective alkylation of threonine‐based oxazoline (I) becomes possible with Baylis—Hillman‐derived allyl bromides or Baylis—Hillman acetates.
ChemInform Abstract: Synthesis and Antiviral Activity of New Substituted Pyrimidine Glycosides.
Authors: Ramiz Mahmoud M. M. , El‐Sayed Wael A. , Hagag Ezzat , Abdel‐Rahman Adel A.‐H. 
Published: January 2012

AbstractThe compounds (I)—(III) are screened for their antiviral activity against hepatitis B virus.
ChemInform Abstract: Synthesis of 4β‐Triazole‐podophyllotoxin Derivatives by Azide—Alkyne Cycloaddition and Biological Evaluation as Potential Antitumor Agents.
Authors: Chen Hong , et al. et al. 
Published: January 2012

AbstractA variety of new 4‐β‐[(4‐substituted)‐1,2,3‐triazol‐1‐yl]podophyllotoxins are synthesized using azide‐alkyne cycloaddition reactions.
ChemInform Abstract: Two New Benzofuranylpropanoids from Nicotiana tabacum and Their anti‐Tobacco Mosaic Virus Activities.
Authors: Tan Jianlin , Chen Zhangyu , Yang Guangyu , Miao Mingming , Chen Yongkuan , Li Tianfei 
Published: January 2012

AbstractNicotfurans A (Ia) and B (Ib) are isolated from the roots and stems of N.tabacum.
ChemInform Abstract: A New Yellowish‐Green‐Emitting Phosphor: Eu2+‐Doped K4CaSi3O9.
Authors: Yuan Beiling , Wang Xigang , Tsuboi Taiju , Huang Yanlin , Seo Hyo Jin 
Published: January 2012

AbstractThe title phosphor is prepared by solid state reaction of a stoichiometric mixture of K2CO3, CaCO3, SiO2, and Eu2O3 with 1.0—5.0 mol% Eu2+ (850 °C for 10 h and 950 °C for 10 h mixed with active carbon).
Regeneration of olfactory afferent axons in the locust brain
Authors: Stern Michael , Scheiblich Hannah , Eickhoff René , Didwischus Nadine , Bicker Gerd 
Published: January 2012

AbstractConfocal image of a locust brain 14 days after one antenna had been crushed. Antennal afferents were anterogradely labeled with Neurobiotin (magenta). Aberrantly regenerated olfactory receptor axons have grown through the antennocerebral tract into the mushroom body. Counterstaining: phalloidin (green) and DAPI (blue). The Journal of Comparative Neurology, Volume 520, Number 4, pages 679‐693.
Synthesis, Molecular Structures, and Reactivity of Dianionic Guanidinate Lanthanide/Lithium Derivatives
Authors: Zhang Xingmin , Qian Cunwei , Wang Chuanyong , Zhang Yong , Wang Yaorong , Yao Yingming , Shen Qi 
Published: January 2012

AbstractAnhydrous LnCl3 was treated with [LiiPrNC(HNiPr)N(C6H4p‐Cl)] and nBuLi at a molar ratio of 1:2:2 in THF to afford heterometallic Ln–Li chlorides stabilized by two dianionic guanidinate ligands [{(iPrN)2C[NLi(THF)3(C6H4p‐Cl)]}2Ln(μ‐Cl2)Li(THF)2]·nTHF [Ln = La (1), Nd (2) n = 2; Sm (3), Yb (4), Y (5) n = 3] in good yields. Treatment of thechlorides with NaOiPr and KOtBu yielded the corresponding isopropoxides [{[(iPrN)2CN(C6H4p‐Cl)Li]2(DME)(LiCl)Ln(OiPr)2}2]2–[{Li(DME)3}+]2·3C6H14 [Ln = Nd (6), Sm (7), Yb (8), Y (9); DME = 1,2‐dimethoxyethane] and tert‐butoxides [{(iPrN)2C(NC6H4p‐Cl)Li(DME)(LiCl)}2Ln(OtBu)2]–[Li(DME)3]+·0.5C6H14 [Ln = Nd (10), Yb (11)]. Attempts to synthesize the corresponding amide and guanidinate complexes by treating 2 with LiNHC6H5 and [LiiPrNC(HNiPr)N(C6H5)] led to the isolation of guanidinate lithium,[LiiPrNC(HNiPr)N(C6H4p‐Cl)(THF)]2 (12). Addition of diisopropylcarbodiimide (iPrN=C=NiPr) into the reaction system of trisguanidinate lanthanide complex [{iPrNHC(NiPr)(NC6H4p‐Cl)}3Yb(THF)] and nBuLi led to the preparation of the first heterometallic Yb–Li complex with a novel biguanidinate ligand [{iPrNHC(NiPr)N(C6H4p‐Cl)}2Yb{(iPrNC(NiPr)2)N(C6H4p‐Cl)C(iPrN)}Li(THF)]·THF (13). The molecular structures of 1–3 and 6–13 were determined by X‐ray crystal structural analysis.
Rain attenuation predictions on terrestrial radio links: differential equations approach
Authors: Abdulrahman A.Y. , Rahman T.A. , Rahim S. K. A. , Islam Md Rafiqul , Abdulrahman M. K. A. 
Published: January 2012

ABSTRACTThe results of rain attenuation on terrestrial microwave links in a tropical climate has been reported in this paper. The results are presented in the form of rate of change of attenuation with respect to rain rate, denoted by S(R%p). This is in turn used for predicting the expected rain attenuation at any %p of the time rain rate is exceeded in any tropical location. The predictions of the proposed model have been validated using the data collected in six locations in Malaysia and experimental results reported in other tropical locations that have a similar rainfall regime. The Malaysian data consist of 1‐year measured rain attenuation over six DIGI MINI‐LINKs operating at 15 GHz, and rainfall rates measured with both 1‐minute and 1‐hour integration times at the respective locations. The validity of the proposed model is further validated by comparing its estimates with the method of ITU‐R Radiocommunication Sector of ITU and two classical rain attenuation prediction models particularly developed for tropical regions. The test results have shown that the proposed method seems to be more accurate than the proposed method seems to be more accurate than ITU‐R and the other two prediction models in Malaysia. The method could be used as an alternative approach for predicting rain attenuation over any terrestrial microwave links in Malaysia and similar tropical climates. Copyright © 2012 John Wiley & Sons, Ltd.
Major moisture sources for Western and Southern India and their role on synoptic‐scale rainfall events
Authors: Ordóñez Paulina , Ribera Pedro , Gallego David , Peña‐Ortiz Cristina 
Published: January 2012

AbstractAlthough the identification of the moisture sources of a region is of prominent importance to characterize precipitation, the origin and amount of moisture towards the Indian Subcontinent and its relationship with the occurrence of precipitation are still not completely understood.In this article, the origin of the atmospheric water arriving to the Western and Southern India during a period of 5 years (1 January 2000–31 December 2004) is investigated by using a Lagrangian diagnosis method. This methodology computes budgets of evaporation minus precipitation by calculating changes in the specific humidity of thousands of air particles aimed to the study area following the observed winds. During the summer monsoon, the main supply of moisture is the Somali Jet, which crosses the equator by the West Indian Ocean. The recycling process is the main water vapour source in winter. Two additional moisture sources located over northwestern India and the Bay of Bengal are identified.A 30% increase in the moisture flux from the Indian Ocean has been related to the occurrence of strong precipitation in the area, and at the end of the monsoon, the recycling became a significant contribution to the last part of the wet season of Western and Southern India. Copyright © 2011 John Wiley & Sons, Ltd.
Calciotropic hormones and the risk of hip and nonspine fractures in older adults: The health ABC study
Authors: Barbour Kamil E , Houston Denise K , Cummings Steven R , Boudreau Robert , Prasad Tanushree , Sheu Yahtyng , Bauer Douglas C , Tooze Janet A , Kritchevsky Stephen B , Tylavsky Frances A , Harris Tamara B , Cauley Jane A ,   for the Health ABC Study
Published: January 2012

Abstract
The effects of vitamin D and parathyroid hormone (PTH) levels on incident fracture remain uncertain. To test the hypothesis that increasing serum 25-hydroxyvitamin D [25(OH)D] and decreasing PTH levels are associated with decreased risk of hip and any nonspine fracture, we conducted a prospective cohort study among 2614 community-dwelling white and black participants, aged ≥70 years, from the Health, Aging and Body Composition (Health ABC) Study. Serum and plasma samples were drawn at year 2, which formed the baseline for this analysis. Serum 25(OH)D and intact PTH (1-84) were measured using radioimmunoassay with DiaSorin reagents and EDTA plasma with a two-site immunoradiometric assay kit, respectively. Incident fractures (hip and any nonspine) were assessed after year 2, every 6 months, by self-report and validated by radiology reports. The median (interquartile range) follow-up times for hip and any nonspine fractures were 6.4 (6.1–6.5) and 6.4 (5.5–6.5) years, respectively. Cox proportional hazards regression was used to estimate the hazard ratios (HR) with 95% confidence intervals (CI) for fracture. There were 84 hip and 247 nonspine fractures that occurred over the follow-up period. The multivariable adjusted HRs (95% CIs) of hip fracture for participants in the lowest (≤17.78 ng/mL), second (17.79 to 24.36 ng/mL), and third quartiles (24.37 to 31.94 ng/mL) of 25(OH)D were 1.92 (0.97 to 3.83), 0.75 (0.32 to 1.72) and 1.86 (1.00 to 3.45), respectively, compared with participants in the highest 25(OH)D quartile (&gt;31.94 ng/mL) (p trend = 0.217). Additional adjustment for IL-6 (p = 0.107), PTH (p = 0.124), and hip areal bone mineral density (p = 0.137) attenuated HRs of hip fracture in the lowest quartile by 16.3%, 17.4%, and 26.1%, respectively. There was no evidence of an association between 25(OH)D and any nonspine fractures, or between PTH and hip or any nonspine fractures. We found limited evidence to support an association between calciotropic hormones and hip and nonspine fractures in older men and women. © 2012 American Society for Bone and Mineral Research.
LTBPs, more than just an escort service
Authors: Todorovic Vesna , Rifkin Daniel B. 
Published: January 2012

AbstractLatent transforming growth factor beta (TGF‐β) binding proteins (LTBPs) are large extracellular glycoproteins structurally similar to fibrillins. They perform intricate and important roles in the extracellular matrix (ECM) and perturbations of their function manifest as a wide range of diseases. LTBPs are major regulators of TGF‐β bioavailability and action. In addition, LTBPs interact with other ECM proteins—from cytokines to large multi‐factorial aggregates like microfibrils and elastic fibers, affecting their genesis, structure, and performance. In the present article, we review recent advancements in the field and relate the complex roles of LTBP in development and homeostasis. J. Cell. Biochem. 113: 410–418, 2012. © 2011 Wiley Periodicals, Inc.
Salicylideneamino‐2‐thiophenol enhances osteogenic differentiation through the activation of MAPK pathways in multipotent bone marrow stem cell
Authors: Kim Hyung Keun , Park Kyung Soon , Lee Jun Sik , Kim Ji Hyun , Park Dae Sung , Shin Jung‐Woog , Yoon Taek Rim 
Published: January 2012

AbstractOsteoporosis is a reduction in skeletal mass due to an imbalance between bone formation and bone resorption. Therefore, the identification of specific stimulators of bone formation is of therapeutic significance in the treatment of osteoporosis. Salicylideneamino‐2‐thiophenol (Sal‐2) consists of two benzene rings, has been reported to possess antioxidant activity, and is an effective remedy for fever and rheumatic diseases. However, until now the effects of osteoblastic bone formation by Sal‐2 were unknown. In this study, we investigated the effects of Sal‐2 on osteogenic differentiation of multipotent bone marrow stromal stem cells by alizarin red S staining for osteogenic differentiation, RT‐PCR and western blot for alkaline phosphatase (ALP) activity and signaling pathways, FACS analysis and immunofluorescence staining for CD44 and CD51 expression, calcium assays, and immunofluorescence staining for signaling pathways. We found that Sal‐2 enhanced the osteogenic differentiation of multipotent bone marrow stromal stem cells. Sal‐2 treatment induced the expression and activity of ALP, and enhanced the levels of CD44 and CD51 expression as well as Ca2+ content, in multipotent bone marrow stromal stem cells. Moreover, we found that Sal‐2‐induced osteogenic differentiation and expression of osteogenesis‐related molecules involve the activation of the MAPK and nuclear factor‐κB pathways. Our findings provide insight into both the mechanism and effects of Sal‐2 on osteogenic differentiation and demonstrate that Sal‐2 may be a beneficial adjuvant in stimulating bone formation in osteoporotic diseases. J. Cell. Biochem. 113: 1833–1841, 2012. © 2012 Wiley Periodicals, Inc.
Two‐step evaluation of binding energy and potential energy surface of van der Waals complexes
Authors: Deshmukh Milind M. , Sakaki Shigeyoshi 
Published: January 2012

AbstractEvaluation of intermolecular distance and binding energy (BE) of van der Waals complex/cluster at ab initio level of theory is computationally demanding when many monomers are involved. Starting from MP2 energy, we reached a two‐step evaluation method of BE of van der Waals complex/cluster through reasonable approximations;
$ {\rm BE} = {\rm BE(HF)} +\sum _{{{\rm M}{i}}>{{\rm M}j}}\{{\rm BE}_{{{\rm M}i}-{{\rm M}j}}({\rm MP2} \ {\rm or} \ {\rm MP}2.5)-{\rm BE}_{{{\rm M}i}-{{M}j}}({\rm HF})\} $
where HF represents the Hartree‐Fock calculation, Mi, Mj, etc. are interacting monomers, and MP2.5 represents the arithmetic mean of MP2 and MP3. The first term is the usual BE of the complex/cluster evaluated at the HF level. The second term is the sum of the difference in two‐body BE between the correlated and HF levels of theory. This equation was applied to various van der Waals complexes consisting of up‐to‐four monomers at MP2 and MP2.5 levels of theory. We found that this method is capable of providing precise estimate of the BE and reproducing well the potential energy surface of van der Waals complexes/clusters; the maximum error of the BE is less than 1 kcal/mol and 1% in most cases except for several limited cases. The origins of error in these cases are discussed in detail. © 2012 Wiley Periodicals, Inc. J Comput Chem, 2012