bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of an Isozyme of β‐Glucosidase from Sweet Almond
Authors: Li Yaw‐Kuen , Chang Li‐Fen , Shu Hsuan‐Hsu , Chir Jiunly 
Published: May 2015

AbstractA sweet almond β‐glucosidase (EC 3.2.1.21) isozyme was purified from commercial crude product. The process of purification consisted of a Protein‐Pak Q anion exchange chromatography following by a Superdex 75 HR gel filtration separation. The purified enzyme is a monomeric glycoprotein with molecular weight of 58 kDa and pI=4.55 which is distinguished from reported isozymes. The enzyme has apH optimum in the range of 5.2‐5.6 when p‐nitrophenyl‐β‐D‐glycopyranosides are used as substrate and is stable up to 50 °C at that pH range. The purified protein also exhibits profound β‐galactosidase and σ‐L‐arabinosidase activity. The study of substrate specificity revealed that lacking of hydroxymethyl group at C‐5 of glycosides resulted in higher affinity for substrate binding to enzyme, whereas the chemical step of hydrolysis (kcst) was prevented significantly. The pH activity profile displayed a bell‐shaped curve for all measured p‐nitrophenyl‐β‐D‐glycopyranosides with apparent pK1 and pK2 values of 4.4‐4.7 and 6.2‐6.4, respectively. This isozyme was strongly inhibited by δ‐gluconolactone (Ki = 160 μM) and 4‐phenylimidazole (Ki = 17.8 μM) reversibly at pH 6.2. Among the tested glycoses, the binding affinity of N‐acetyl‐β‐D‐glucosamine to the enzyme (Kl = 52 mM) was 6 times stronger than that of glucose and its epimers.
A Cyclization Approach toward Five‐Membered Heteroaromatico‐QuinodimethanesviaFused‐3‐Sulfolenes
Authors: Chou Ta‐Shue , Tsai Chung‐Ying , Lee Shwu‐Jiuan 
Published: May 2015

AbstractA general strategy involving the zincation of 4‐bromo‐3‐chloro‐2‐sulfolene,in situcondensation with an α‐heterosubstituted acetaldehyde, and subsequent cyclization reaction as the key steps toward the synthesis of furano‐ and thieno‐3‐sulfolenes is described. These fused‐3‐sulfolenes are demonstrated to be good precursors for the correspondingo‐quinodimethanes.
Derivatization, Separation and Determination of Steroids and Triterpenoids by Reverse‐Phase HPLC and UV Detection
Authors: Wang Shu‐Ping , Lai Jeng‐Shiow , Lin Shaw‐Tao 
Published: May 2015

AbstractThe steroids were derivatised with aroyl chloride to yield the corresponding benzoates. Among them, their 4‐methoxybenzoates were obtained in greatest yield and were analyzed by HPLC with the smallest detection limit (10 ng) by means of a UV detector (254 nm). This method of derivatization can be applied for analysis of steroids and triterpenoids from crude products with the HPLC technique.
Nascent Rotational Distributions of MgH in Reaction of Mg(4s 1S0) with H2 and HD
Authors: Liu Dean‐Kuo , Lin King‐Chuen 
Published: May 2015

AbstractThe nascent rotational distributions of MgH(X2σ+, v″ = 0, 1) resulting from the reaction of Mg(4s1S0) with H2 and HD have been determined by using the laser pump‐probe technique. Like the case of Mg(1P1), the distributions appear to be bimodal which peak mainly at high N(26) with minor peaks at low N(6). There are no apparent differences when the escaping mass is doubled. The similarity between product rotational distributions from the 4S state and those from the 3P state, and no evidence of a kinematic isotope effect, reveal that a harpoon‐type mechanism may be operative. Our ab initio calculations reveal that in the entrance channel on the 31A1 surface in C2v symmetry or 1σ+ surface in C∞v symmetry for 4S state, the reaction may lake place via a series of non‐adiabatic curve crossings with the ionic Mg+H2− potential surface.
Phenolics from Acalypha indica
Authors: Ma Ying‐Tsun , Chuang Jin‐I , Lin Jer‐Huei , Hsu Feng‐Lin 
Published: May 2015

AbstractTwo novel hydrolysable tannins, potassium brevifolincarboxylate and acaindinin, together with eight known tannins—1‐O‐galloyl‐β‐D‐glucose, 1,2,3,6‐tetra‐D‐galloyl‐β‐D‐glucose, corilagin, geraniin, acetonylgeraniin A, euphormisin M2, repandusinic acid A, and chebulagic acid, as well as two flavonoid glycosides — quercetin 3‐O‐β‐D‐glucoside and rutin, were isolated from Acalypha indica. Their structures were elucidated on the basis of chemical and spectroscopic evidence.
Chiral Alkoxy Side Chains from (‐)‐Amino Acids in Mediating Asymmetric Synthesis of Tricarbonyl(cyclohexadienyl)iron Complexes
Authors: Chang Tsu‐Hsin , Kuo Chien‐Ren , Ong Chi‐Wi 
Published: May 2015

AbstractThe asymmetric induction in the complexation reaction of (S)‐1‐methyl‐2‐(5‐methyl‐cyclohexa‐1,4‐dienylmethyloxy)‐pyrrolidine 5 and (S)‐2‐(2‐N,N‐dimethylamino‐1‐propanoxy)‐5‐methylcyclohexa‐1,4‐diene 6 having heteroatom adjacent the stereogenic center has been investigated. The diastereoselectivity was determined directly from the diastereotopic peaks in the 1H NMR or by chemical correlation with 9. The conversion of η‐1,4‐complexes 7a and 8a to 9 proceeded with high retention of configuration while that of the η‐2,5‐Fe(CO)3 complexes 7b and 8b undergoes considerable racemization.
First Total Synthesis of 1,2‐Dehydronephthenol
Authors: Li Weidong , Qu Jin , Li Jing , Li Ying , Li Yulin 
Published: May 2015

AbstractThe first total synthesis of 1,2‐Dehydronephthenol (15‐hydroxy‐cembra‐1,3,7,11‐tetraene), a novel cembranoid diterpene, was accomplished starting from trans, trans‐farnesol through seven steps in an overall yield of 17% by employing titanium‐induced intramolecular keto aldehyde reductive olefination‐coupling as the key macrocyclization step.
Photochemistry of Substituted 4,4‐Dimethoxy‐2,5‐Cyclohexadienones
Authors: Hong Fang‐Tsao , Lee Kung‐Shing , Tsai Yow‐Fu , Liao Chun‐Chen 
Published: May 2015

Abstract4,4‐Dimethoxy‐2,5‐cyclohexadienones 9–14 were prepared from the corresponding hydroquinone monomethyl ethers by oxidation with thallium trinitrate in methanol. Irradiation of solutions of 9–13 in methanol with a broad band of UV light centered at 350 nm in a Rayonet reactor afforded 2‐cyclopentenone derivatives 15–19 in moderate to excellent yields, whereas irradiation of 14 in methanol gave phenol 8 along with other unidentified products. Irradiation of 11–14 in benzene yielded substituted phenols. The plausible reaction pathways for the product formation are discussed.
Bond Alternation and Energy Increment in Linear and Angular Isomers of [N]Phenylenes
Authors: Lin Chiu‐Ling , Chu San‐Yan , Ou Ming‐Chiu 
Published: May 2015

AbstractFrom recent accurate ab initio calculation on [N]phenylenes by Schulman and Disch, some regular patterns for bond alternation and energy increment can be found. We interpreted these results by considering a “unit cell” of interior benzene rings fused to two four‐membered rings in either linear or angular fashion. Our model works better in accounting for the structure than for the energy.
The Application of Chelating Agent Incorporated Polymer Modified Electrodes in the Detection of Trace Metals
Authors: Zen J.‐M. , Lee M.‐L. , Huang S.‐Y. , Hsu F.‐S. , Chi N.‐Y. , Chung M.‐J. 
Published: May 2015

AbstractThe use of chelating agent‐modified Nafion®‐coated mercury‐film electrodes (CNCMFEs) in square wave anodic stripping voltammetry (SWASV) for the determination of trace metals is described. The CNCMFE containing appropriate amounts of dimethylglyoxime (DMG) was applied for the determination of Ni(II), Cd(II), and Cu(II). A similar system that contains 2,2′‐bipyridyl (Bpy) was used for the determination of Pb(II). The effect of various model organic substances on the CNCMFEs in SWASV is thoroughly explored. The CNCMFEs are considerably more resistant to organic interferences than the Nafion®‐coated MFE. The implications of these interferences for the reliability and feasibility of stripping measurements using the CNCMFEs in real samples are discussed. Results presented for real samples demonstrate the analytical utility of the CNCMFEs in SWASV.
Molecular Structure of Bis(2,2′‐bipyridine)dioxovanadium(V) Trifluoromethanesulfonate
Authors: Su Chan‐Cheng , Huang Gin‐Song , Liu Shyh‐Jiun , Wang Sue‐Lein , Liao Fen‐Ling 
Published: May 2015

AbstractBis(2,2′‐bipyridine)dioxovanadium(V) trifluoromethanesulfonate, obtained from autooxidation of the corresponding oxovanadium(IV) complex, crystallizes in monoclinic, P21/n, with a = 15.433(2), b = 11.013(2), c = 27.423(2) Å, β = 104.79(2)°, Z = 4, R = 0.0697, and Rw = 0.0821. The complex consists of discrete vanadium(V) complex cations and trifluoromethanesulfonate anions. Each asymmetric unit is composed of a pair of enantiomer molecules. The octahedral vanadium complex ion, having a C2 axis, comprises a cis‐VO2, mean V‐O distance of 1.622 ± 0.007 Å, and two cis‐related 2,2′‐bipyridine ligands. The V‐N bonds trans to each other are short, with a mean V‐N distance of 2.108 ± 0.010 Å, while those trans to V=O are somewhat longer, with a mean V‐N distance of 2.292 ± 0.022 Å. The coordination geometry of the vanadium cation is very similar to that of [VO(O2)(2,2′‐bipyridine)2]+.
Molecular Structure of a New Tetrameric μ4‐oxo‐Cu(II)4 Complex Derived from the Dicopper(I) Complex of 4‐Methyl‐2,6‐bis(pyrazol‐1‐ylmethyl)phenolate and Molecular Oxygen
Authors: Chen Chun‐Tong , Sheu Shiann‐Chemg , Lee Gene‐Hsiang , Ho Tong‐Ing , Wang Yu , Lin Yuan‐Chuan , Oliver Su Y. 
Published: May 2015

AbstractA new dicopper(I) complex of 4‐methyl‐2,6‐bis(pyrazol‐1‐ylmethyl)phenolate (LOH) has been synthesized by the reaction of LOH with Cul to form LOHCu2I2(1), which catalyzes the oxidation of 3,5‐di(t‐butyl)catechol. LOHCu2I2 reacts with molecular oxygen to form a peroxo‐dicopper(II) complex and undergoes cleavage of 0–0 bridge to give a new μ4‐oxo‐Cu11 tetramer with seven‐membered ring coordination as characterized by X‐ray crystallography.
Sodium Aristolochates from the Flowers and Fruits of Aristolochia zollingeriana
Authors: Chiang Chia‐Yu , Leu Yann‐Lii , Chan Yu‐Yi , Wu Tian‐Shung 
Published: May 2015

AbstractTwo new sodium salts of aristolochic acids: sodium aristolochate‐II and ‐IVa, together with ten known compounds: sodium aristolochate‐I, sodium aristolochate‐C, aristolactam, aristolactam‐N‐β‐D‐glucoside, cepharadione‐A, 3,5‐pyridinedicarboxamide, p‐hydroxybenzaldehyde, trans‐methyl p‐coumarate, 6‐hydroxy sitost‐4‐en‐3‐one, β‐sitosterone and β‐sitosterol, and stigmasterol mixture were isolated from the fresh flowers and fruits of Aristolochia zollingeriatia. Their structures were deterimined by spectral and chemical methods. IR and 1H NMR methods to distinguish aristolochic acid from its salt are discussed.
Three New Naphthoquinones from the Stem of Diospyros maritime Blume
Authors: Kuo Yue‐Hsiung , Chang Chi‐I , Kuo Yao‐Haur , Huang Shou‐Ling 
Published: May 2015

AbstractThree new naphthoquinone derivatives, isolated from the stems of Diospyros maritima Blume, were elucidated as 2′‐ethoxyisodiospyrin, 3′‐ethoxyisodiospyrin, and 3‐ethoxyisodiospyrin, respectively, on the basis of spectral properties.
Identification of Bioactive Components in Antrodia cinnamomea by MS/MS via El Ionization
Authors: Young Dun‐Shyumg , Chiang Hung‐Cheh , Liu Lilian Kao 
Published: May 2015

Abstract4α‐Methylergosta‐8,24(28)‐dien‐3,7,11‐trion‐26‐oic acid and 4α‐methylergosta‐8,24(28)‐dien‐3,11‐dion‐7β‐ol‐26‐oic acid are two clinically active components found in Antrodia cinnamomea. Using the specific fragmentation in their mass spectra together with the ratio of these diagnostic ions in their respective SIM mass spectra, and/or their MS/MS spectra, a fast, simple, and efficient mass spectral method has been developed for identification of these compounds in Antrodia cinnamomea preparations without prior isolation of the individual compound.
Product Selectivity in Photoelectrochemical Reduction of Benzyl Halides on Semiconductor Photocathodes
Authors: Tsunashima Katsuhiko , Nonaka Tsutomu 
Published: May 2015

AbstractElectrochemical reduction of benzyl halides on various cathodes was examined under illumination and in the dark. Product selectivity control in the reduction by illumination was accomplished only when p‐type semiconductor photocathodes were used. By estimating the electrophilicity of benzyl halides from their rate constants for methanolysis under illumination and in the dark, it was proposed that the mechanism for the selectivity control by illumination involves a photo‐assisted process for the nucleophilic attack of carbanion intermediate species formed by the two‐electron reduction of the benzyl halides to the unreacted ones as electrophiles.
Ene Reaction of Pummerer‐Type Reaction Intermediate and Synthesis of Pellitorine
Authors: Lin Wei‐Shing , Wang Hucy‐Min , Chen Ling‐Ching 
Published: May 2015

AbstractPummerer‐type reaction intermediate 2 of α‐(methylthio)acetic acid (1) has been found to react with 1‐alkenes to afford ene adducts 3. Pellitorine 5 was synthesized from the adduct 3d.
Ultrasonic Effects on Electroorganic Processes. Part 10. Product‐Selectivity in Mixed Kolbe Electrolysis of Carboxylic Acids
Authors: Fujiwara Hiroki , Atobe Mahito , Kanetsuna Hidenori , Nonaka Tsutomu 
Published: May 2015

AbstractProduct‐selectivity was examined in mixed Kolbe electrolysis of carboxylic acids on a platinum anode in aqueous methanolic solutions under ultrasonic irradiation. It was found that an ultrasonic effect on the selectivity is caused not only by promotion of mass transport across the electrode interface but also by adsorption control of intermediated radical species by ultrasonic acoustic and cavitation effects. Namely, formation of the one‐electron oxidation products is favourable at low current densities compared with two‐electron oxidation products under irradiation, while the two‐electron oxidation is promoted at high current density. This is the ultrasonic effect characteristic of the Kolbe electrolysis. The mechanism of the ultrasonic effect is discussed with a hypothesis.
Nitration of 2‐Aryl‐1,1‐dihalocyclopropanes Containing Methyl or Phenyl Group
Authors: Lin Lee‐Huey , Lin Shaw‐Tao , Yang Hucy‐Ju 
Published: May 2015

AbstractGem‐dihalocyclopropanes bearing a phenyl group and an additional group were nitrated by using nitric acid in a sulfuric acid matrix. The products from the nitration of aryl rings are major. The presence of a methyl group on the C(2) position of the cyclopropane ring leads to the isoxazoline from nitration at the C(1)‐position instead of that from nitration at the C(2)‐position.
Synthesis and Characterization of Amino‐Functionalized PDPS/PDMS Copolymers
Authors: Yang Mei‐Hui , Chou Chyuan , Lin Chih‐Hwa 
Published: May 2015

AbstractVarious amino‐functionalized polysiloxanes were synthesized in high yields (∼90%) via ring‐opening polymerization of cyclic siloxane monomers through either bulk or solution process. The amino‐functionality was introduced through adding (MeO)2MeSiC3H6NHC2H4NH2 (A) or NH2C3H6(Me)2SiOSi(Me)2‐C3H6NH2 (B) as terminators and/or as reagents mixed with monomers initially. The bulk polymerization of D4 and P4 was initiated with potassium salts such as Me3SiOK or KOH, while the solution living polymerization of D3 and P3 was initiated with LiOH in THF or toluene solution. The optimum conditions for preparing copolymers with different structure types were studied. The purity of the products determined by silica gel column chromatography was found to be higher than 98%. All of the copolymers were characterized with GPC, 1H NMR, and DSC techniques. The silyl derivatives of primary amines were used in GPC characterization. The number‐average molecular weights determined by 1H NMR and those determined by GPC measurements were in excellent agreement. The aminosilane A served either as a terminator, which gave an amino‐terminated polysiloxane, or a reagent which was mixed with comonomers initially and incorporated into the copolymerization to give a side‐chain aminopolysiloxane. When A was used as a terminator, no insertion of A into the copolymer was found. In addition, the molecular weights of the copolymers can be controlled by the amount of terminating aminosilanes added into the system.
Chemical Constituents from Mucuna membranacea
Authors: Lin Yun‐Lian , Tsai Wei‐Jern , Chen Ih‐Sheng , Kuo Yueb‐Hsiung 
Published: May 2015

AbstractAntiplatelet‐directed fractionation of the ethanolic extract from the root of Mucuna membranacea Hayata resulted in the isolation of friedelin (1), friedelanol (2), β‐sitosterol (3a) & stigmasterol (3b), trans‐p‐coumaric acid (4), protocatechuic acid (5), vanillic acid (6), and flavonoids — geraldol (7), 3′‐methoxydaidzein (8), genistein (9), daidzein (10), cyclosin (11), formononetin (12), orbol (13), isoformononetin (14), pratensein (15) and luteolin (16). Their structures were elucidated on the basis of spectral methods. Compounds 7 and 8 were tested for the antiplatelet aggregation activity and appeared to be specific against collagen‐induced platelet aggregation with a IC50 values of 61.5 and 12.3 μM, respectively.
Silver(I) Complexes of Schiff Bases Derived from Thiophene‐2,5‐dicarboxaldehyde and Furan‐2,5‐dicarboxaldehyde
Authors: Hwang Wen‐Shu , Wang Dong‐Liang , Hsu Sen‐T'sing , Liu Ling‐Kang 
Published: May 2015

AbstractThe reactions of Schiff bases, derived by the condensation of thiophene‐2,5‐dicarbaldehyde and furan‐2,5‐dicarbaldehyde with 2‐thienylmethylamine or 2‐furanmethylamine, with silver nitrate have been studied in refluxing anhydrous methanol under nitrogen atmosphere. Complexes thus formed have been isolated and characterized by elemental analysis, electrical conductance, cyclic voltammetry, and 1H NMR, 13C NMR, IR, LTV‐Vis, and mass spectroscopic studies. The experimental results reveal that the complexes are primarily ionic in nature, consisting of (L)3Ag2 dication and Ag(NO3)3 negatively charged dianions. The molecular structure of one of the complexes, [((C4H3O)CH2NCH(C4H2S)CHNCH2(C4H3O))3Ag2] [Ag(NO3)3] has been studied in the solid state. The complex is crystallized in the triclinic space group \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm P}\bar 1 $\end{document} with a = 12.889(7) Å, b = 14.884(5) Å, c = 15.084(6) Å, α = 92.18(4)°, β = 79.78(4)°, γ = 110.92(4)°. The structure is disordered. Each Ag in dication is tri‐coordinated by three azomethine N atoms from three ligands, and each ligand employs two azomethine N atoms to coordinate to two Ag ions such that the geometry around the Ag ⃜Ag axis conforms to a propeller‐shape. The two Ag ions are between the two N3 planes with Ag ⃜ Ag distance ca. 4.8.1 Å. There is no bonding between any Ag ion and any thiophene of the three ligands. However, two Ag ions and three thiophene S atoms form a trigonal bipyramidal geometry.
Photorearrangement of Propargyl Bromide as a Probe to Study Propargylic and Allenic Radicals by Infrared Matrix Isolation Technique
Authors: Wu Yuh‐Wern , Hwang Mei‐Lee , Hsu Wei‐Liang , Fang Fen‐Hui 
Published: May 2015

AbstractThe photolysis of propargyl bromide in Ar matrix to form allenyl bromide proceeded with a radical mechanism. The deuterium label study and radical scavenger were used to investigate the mechanism. Neither propargyl nor allenyl radical was trapped in Ar matrix at 8 K. The rates of propargyl and allenyl radicals coupled with bromo radical are significantly fast. The stability of propargyl and allenyl radicals is discussed.
Synthesis of Imidazo[4,5‐b]quinoxaline Ribonucleosides as Linear Dimensional Analogs of Antiviral Polyhalogenated Benzimidazole Ribonucleosides
Authors: Zhu Zhijian , Saluja Sunita , Drach John C. , Townsend Leroy B. 
Published: May 2015

AbstractWe have recently found that 2,5,6‐trichloro‐1‐(β‐D‐ribofuranosyl)benzimidazole (TCRB) and the corresponding 2‐bromo analog have better in vitro activities against HCMV than the clinically used agents ganciclovir and foscarnet. These benzimidazole nucleosides act by a unique mechanism, however, their biological target has not been completely identified. As an approach to probing the target, we have designed imidazo[4,5‐b]quinoxaline nucleosides as linear dimensional analogs of the benzimidazole nucleosides to study the spatial limitation of the binding site in the target enzyme. A convenient route was developed for the synthesis of 2‐substituted 6,7‐dichloroimidazo[4,5‐b]quinoxalines involving a reaction of 2,3,6,7‐tetrachloroquinoxaline with ammonia followed by a ring annulation as the key step. This furnished the versatile heterocycle 6,7‐dichloroimidazo[4,5‐b]quinoxalin‐2‐one. Ribosylation of 2‐substituted imidazo[4,5‐b]quinoxalines was influenced by the functional group at the 2‐position and the 2‐one compound was found to smoothly undergo ribosylation. The 2‐one group of the nucleoside was converted into specifically selected 2‐substituted compounds. Evaluation of the compounds for activity against two herpesviruses and for cytotoxicity showed they were less active and/or more cytotoxic than TCRB. We conclude therefore, that the binding pocket on the protein target of TCRB will tolerate some electronic and size changes.
On the Electric Field Effect on the Dynamics of High Rydberg States of Hydrogen Atom and the Model of ZEKE Spectroscopy
Authors: Chao S. D. , Hayashi M. , Lin S. H. , Schlag E. W. 
Published: May 2015

AbstractIn this paper, the studies of the dynamics of the high Rydberg states for n = 10 and n = 100 of hydrogen atom under the influence of an electric field will be reported. It will be shown from our calculated results that the two time constants of τslow ≈︁ 1 – 10 μs and τfast ≈︁ 1 – 10 ns obseved in ZEKE experiments are obtained in the stray field condition, i.e., F = 10 – 100 mV/cm. To treat the ZEKE states of complex systems like many‐electron atoms, molecules, clusters etc., the inverse Born‐Oppenheimer approximation can be used and it will be discussed.
The Constituents of the Stem and Roots of Aristolochia foveolata
Authors: Leu Yann‐Lii , Chan Yu‐Yi , Hsu Meei‐Yu , Chen Ih‐Sheng , Wu Tian‐Shung 
Published: May 2015

AbstractOne new aristolactam glucoside: aristolactam‐Ia‐N‐D‐glucoside together with seventeen known compounds were isolated from the fresh stems and roots of Aristolochia foveolata. Their structures were determined by spectral and chemical methods. Among seven aristolochic acid derivatives, five were determined to be salt forms by IR and 1H NMR methods.
Study of Host‐Guest Complexation of Alkaline Earth Metal Ion, Aluminum Ion and Transition Metal Ions with Crown Ethers by Fast Atom Bombardment Mass Spectrometry
Authors: Wu Hui‐Fcn , Chen Li‐Wei 
Published: May 2015

AbstractComplexations of crown ethers with alkali metal ions have been investigated extensively by FAB mass spectrometry over the past decade, but very little attention has been paid to reactions of crown ethers with other classes of metal ions such as alkaline earth metal ions, transition metal ions and aluminum ions. Although fast atom bombardment ionization mass spectrometry has proven to be a rapid and convenient method to determine the binding interactions of crown ethers with metal ions, problems in reliabilities for quantitative measurements of” binding strength for the host‐guest complexes have been described in the literature. Thus, in this paper, applications of FAB/MS for investigating the complexation of crown ethers with various classes of metal ions is discussed. Extensive fragmentations for neutral losses such as C2H4O or C2H4 molecules from the host‐guest complexes could be observed. The reason is attributed to the energetic bombardment processes of FAB occuring in the formation of these complexes. Complexes of cyclen with metal ions also show neutral losses of C2H4NH molecules leading to fragment ions. Transition metal ions usually form (Crown + MCl)+ type of ions, alkaline earth metal ions can form both (Crown + MCl)+ and (Crown + MOH)+ type of ions. But for aluminum ions, only (Crown + Al(OH)2)+ type of ions could he observed.