Odd Number Of Methylene Groups Research Articles

An integrated cofactor and co-substrate recycling pathway for the biosynthesis of 1,5-pentanediol

Background1,5-pentanediol (1,5-PDO) is a linear diol with an odd number of methylene groups, which is an important raw material for polyurethane production. In recent years, the chemical methods have been predominantly employed for synthesizing 1,5-PDO. However, with the increasing emphasis on environmentally friendly production, it has been a growing interest in the biosynthesis of 1,5-PDO. Due to the limited availability of only three reported feasible biosynthesis pathways, we developed a new biosynthetic pathway to form a cell factory in Escherichia coli to produce 1,5-PDO.ResultsIn this study, we reported an artificial pathway for the synthesis of 1,5-PDO from lysine with an integrated cofactor and co-substrate recycling and also evaluated its feasibility in E.coli. To get through the pathway, we first screened aminotransferases originated from different organisms to identify the enzyme that could successfully transfer two amines from cadaverine, and thus GabT from E. coli was characterized. It was then cascaded with lysine decarboxylase and alcohol dehydrogenase from E. coli to achieve the whole-cell production of 1,5-PDO from lysine. To improve the whole-cell activity for 1,5-PDO production, we employed a protein scaffold of EutM for GabT assembly and glutamate dehydrogenase was also validated for the recycling of NADPH and α-ketoglutaric acid (α-KG). After optimizing the cultivation and bioconversion conditions, the titer of 1,5-PDO reached 4.03 mM.ConclusionWe established a novel pathway for 1,5-PDO production through two consecutive transamination reaction from cadaverine, and also integrated cofactor and co-substrate recycling system, which provided an alternative option for the biosynthesis of 1,5-PDO.

Synthesis of Octacalcium Phosphate Containing Glutarate Ions with a High Incorporation Fraction.

Octacalcium phosphate (OCP) has received considerable attention in the field of ceramic biomaterials as an advanced functional material. It exhibits a layered structure composed of apatitic and hydrated layers and can incorporate various dicarboxylate ions into the hydrated layer. Saturated dicarboxylic acids (HOOC(CH2)nCOOH) with an odd number of methylene groups (-CH2-) exhibit lower incorporation fractions than those with an even number of methylene groups, possibly owing to a compositional dependence on the synthetic method. In this study, calcium carbonate, phosphoric acid, and various amounts of glutaric acid were used to produce glutarate-ion-incorporated OCP by a wet chemical method, which is different from the conventional synthetic strategy. While utilising 1-20 mmol of glutaric acid during synthesis did not produce the desired product, using 25 mmol of glutaric acid resulted in the formation of single-phase glutarate-ion-incorporated OCP with a Ca/P molar ratio of 1.57 and a 90% incorporation fraction of glutarate ions. This glutarate-ion-incorporation fraction is significantly higher than that reported in the previous studies (35%). Thus, the synthetic procedure proposed herein was able to produce single-phase OCP containing glutarate ions with a high incorporation fraction. Our findings can contribute to development of novel functional ceramic biomaterials in the future.

Oligomeric odd–even effect in liquid crystals

We demonstrate a novel oligomeric odd–even effect of mesogenic segments connected by flexible chains with an odd number of methylene groups.

Anomalous Increase in Nematic-Isotropic Transition Temperature in Dimer Molecules Induced by a Magnetic Field.

We have determined the nematic-isotropic transition temperature as a function of an applied magnetic field in three different thermotropic liquid crystalline dimers. These molecules are comprised of two rigid calamitic moieties joined end to end by flexible spacers with odd numbers of methylene groups. They show an unprecedented magnetic field enhancement of nematic order in that the transition temperature is increased by up to 15K when subjected to a 22T magnetic field. The increase is conjectured to be caused by a magnetic-field-induced decrease of the average bend angle in the aliphatic spacers connecting the rigid mesogenic units of the dimers.

New poly(pentylene furanoate) and poly(heptylene furanoate) sustainable polyesters from diols with odd methylene groups

In the current manuscript two new furan based polyesters, namely poly(pentylene furanoate) (PPeF) and poly(heptylene furanoate) (PHepF), have been synthesized for the first time using 2,5-furandicarboxylic acid (2,5-FDCA) and aliphatic diols with odd number of methylene groups (5 and 7 respectively) via melt polycondensation method. Their structural characteristics and thermal properties are presented in detail.

On the twist-bend nematic phase formed directly from the isotropic phase

The intriguing twist-bend nematic (NTB) phase is formed, primarily, by liquid crystal dimers having odd spacers. Typically, the phase is preceded by a nematic (N) phase via a weak first-order transition. Our aim is to obtain dimers where the NTB phase is formed directly from the isotropic (I) phase via a strong first-order phase transition. The analogy between such behaviour and that of the smectic A (SmA)–N–I sequence suggests that this new dimer will require a short spacer. This expectation is consistent with the prediction of a molecular field theory, since the decrease in the spacer length results in an increase in the molecular curvature. A vector of odd dimers based on benzoyloxybenzylidene mesogenic groups with terminal ethoxy groups has been synthesised with spacers composed of odd numbers of methylene groups. Spacers having 5, 7, 9 and 11 methylene groups are found to possess the conventional phase sequence NTB–N–I; surprisingly, for the propane spacer, the NTB phase is formed directly from the I phase. The properties of these dimers have been studied with care to ensure that the identification of the NTB phase is reliable.

Even–odd effect in the co-crystals of pyrazine and dicarboxylic acids

The co-crystals of pyrazine with dicarboxylic acids of the form (COOH)–(CH2)n–COOH: oxalic (n = 0), malonic (n = 1) succinic (n = 2), glutaric (n = 3), adipic (n = 4), and pimelic (n = 5) acid, were synthesized and structurally characterized by means of X-ray diffraction. There are two principal structural motifs, depending on the stoichiometry: for 1:1 co-crystals, there are chains of alternate pyrazine and acid molecules, connected by strong O–H···N hydrogen bonds (···pyr···acid···pyr···acid···) while for 2:1 stoichiometry the chains are made of pyrazine molecules and carboxylic acid centrosymmetric dimers (···pyr···acid···acid···pyr···). The first possibility is observed for all acids in the series, while the second one only for these with odd numbers of methylene groups. The geometrical features of the acids do not show the clear indication for a reason of such behavior, the most probable reason can be connected with the possible symmetry of the acid molecule, C i for n even, and with the mutual orientation of terminal carbonyl and hydroxyl groups, defined by improper O=C···C=O torsion angles, which are close to 180° for even and have much smaller values for odd n values.

Structures and phase transformations of odd-numbered asymmetric main-chain liquid crystalline polyesters

Two new asymmetric odd-numbered main-chain liquid crystalline (LC) polyesters (BPE-Cn) were synthesized through the condensation polymerization of A–B type asymmetric α,ω-carboxylic acid–hydroxyl terminated monomers with odd-numbers of methylene units in the spacers (BPCA-Cn-PmOH, where n=7 and 9). The phase behaviors and structures of these odd-numbered BPE-Cn samples were characterized using the combined techniques of differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), selected area electron diffraction (SAED) and polarized light microscopy (PLM). One-dimensional (1D) powder WAXD results at different temperatures combined with DSC results revealed that during cooling these two polyesters enter a low-ordered LC phase before developing a crystalline phase at lower temperatures. Based on 2D WAXD of oriented fiber patterns, the low ordered LC phase of odd-numbered BPE-Cn was identified to be a smectic A (SmA) phase, which was constructed by each chemical repeating unit along the fiber drawn direction. The crystalline structures were determined to be monoclinic unit cells (KM). However, BPE-C7 possessed a γ=87°, while BPE-C9 had a β=100°. These crystalline structure identifications were also confirmed by SAED from single crystals. Two-chain packing models of the KM phases with four chemical repeating units were proposed on the basis of the experimental diffraction patterns. The different structures were attributed to the interplay between the mesogenic group ordering propensity and the chain constraints dictated by the methylene spacer and the meta-linkage at the end of mesogen. In the ordered phases of these two odd-numbered BPE-Cn polyesters, aromatic mesogenic groups are more or less parallel to each other along the chain with small angles of deviation from the c-axis of the crystal lattice, different from those large zigzag conformation structures in even-numbered BPE-Cn crystals. Crystallographic calculations of these two unit cell structures indicated that the neighboring chains in the crystals are translated along the c-axis (in the case of BPE-C9) or twisted away from the b-axis (in the case of BPE-C7) in order to incorporate both of the bend attributed to the odd-numbered methylene spacers and of the configurational meta-linkage at the end of mesogens. The simulated diffractions based on these calculations qualitatively agreed with the experimental observations. The phase identifications were also supported by the observed texture changes in PLM.

Odd-even chain length-dependent order in pH-switchable self-assembled layers.

The reversible self-assembly of a series of bipolar amphiphiles, alpha,omega-bis(3- or 4-amidinophenoxy)alkanes (chain length n = 5-12), on mercaptoalkanoic acid-functionalized gold surfaces (chain length n = 10, 11, 14, 15) has been studied by in-situ ellipsometry, IR reflection absorption spectroscopy (IRAS), and atomic force microscopy (AFM). The layer order, amphiphile orientation, and tendency to form bilayers depends on the position of the amidine substituent, the alkyl chain length of both the amidine amphiphile and the underlying acid self-assembled monolayer (SAM), and whether the amidine alkyl chain contained an even or odd number of methylene groups. Thus, para-substituted bisbenzamidines containing more than six methylene groups (n>6) and with an odd number (n = 7, 9, 11) tended to form bilayered structures, whereas those containing an even number formed monolayers when adsorbed on SAMs of the long-chain acids (n = 14, 15). This behavior also correlated with the average tilt angle of the benzene moieties of the amphiphiles, as estimated by IRAS. The odd-numbered chains gave lower tilt angles than the even-numbered ones, and a possible model that accounts for these results is proposed. IRAS also revealed a higher order of the odd-numbered chains and an increasing hydrogen-bonding contribution with increasing chain length. Additional evidence for the proposed bilayered assemblies and their reversibility was obtained by AFM. Images obtained from the assembly of decamidine on a SAM of mercaptohexadecanoic acid in a pH 9 borate buffer revealed domains of similar size to that of the underlying acid SAM (20-30 nm), but less densely packed. By acidifying the solution, the second layer was destabilized and a very smooth layer with few defects appeared. Further acidification to pH 3 also destabilized the first layer.

Poly(ether-ester) multiblock copolymers based on poly(oxymethylene-alt-oxyalkylene) glycols

Alternating polyols of oxymethylene and oxyalkylene were synthesized and used as precursors for thermoplastic poly(ether-ester) elastomers (TPEs). The polyols were synthesized by reacting diols having different methylene units with dichloromethane in the presence of a phase transfer catalyst. The number of methylene units in the alkylene oxides was varied from 3 to 6. TPEs were prepared using the polyols as soft segments and poly(butylene terephthalate) units as hard segments. The polyols and TPEs synthesized were characterized using FTIR, NMR, GPC, DSC, and polarized optical microscopy. The polyols showed a profound odd-even effect on the melting(Tm) and glass transition temperatures(Tg). Polyols with odd numbers of methylene groups in the alkylene units have higher transition temperatures than polyols with odd number of methylene groups. The tendency is still kept in TPEs, even though theTg of soft segment in TPEs are slightly higher than those of corresponding neat polyols. TheTm andTg of soft segments are almost constant in the range of 20 to 60 wt % contents of soft segments. On the other hand, the normalized heat of fusion of hard segment decreased with increasing the content of soft segment.

Corrosion Protection by Self-Assembly

The inhibition effect and properties of adsorption layers formed by molecule series α,ω-diphosphono-alkane on iron surface are investigated. A significant difference is obtained in inhibition effect between compounds having alkyl chains with odd and even numbers of carbon atoms; better protection can be achieved by use of diphosphonates containing odd numbers of methylene groups. The best corrosion inhibition could be attained with 1,7-diphosphono-heptane (1,7-DPH). It is found that a certain threshold concentration of the diphosphonate (c > 4 × 10–4 M) is necessary to ensure sufficient inhibition. The influence of solution concentration on inhibition effect can be interpreted with the layer formation properties and the surfactant nature of molecules. A significant effect of the diphosphonate is appeared on the kinetic of anodic iron dissolution process. Diphosphonates act as anodic inhibitors, the inhibitor layer formation results in a passivation of the metal surface. Well-ordered self-assembled layer with high corrosion protection effect is obtained in aqueous solution of α,ω-diphosphonic acids. The self-assembly process takes a longer time, few days are necessary to reach the optimal organization of adsorbed organic layer. It is found that aqueous conditions are preferred for the protective layer formation. It is supposed that with simple chemical surface modification, i.e. with immersion of iron into the solution of alkane-diphosphonates, a new surface pre-treatment could be developed.

NONLINEAR OPTICAL PROPERTIES OF MOLECULAR TWINS

Three different series of twin nonlinear optic (NLO) molecules were studied, in which the two NLO chromophores are linked by a central flexible polymethylene spacer. The first series, which had two azobenzene chromophores (Azo-twins), was designed to also exhibit liquid crystallinity. Most of the members of this series exhibited a nematic mesophase. The second series had two 4-nitrophenol units as chromphores (PNP-twins), while the third one was based on 4-alkylsulfonyl-4'-alkoxy azobenzene chromophores (Sulfazo-twins). These twin NLO systems exhibited interesting odd-even oscillations in their second harmonic generation (SHG) efficiencies in the powder form. When the spacer had an odd number of methylene groups, they exhibited significantly higher powder SHG efficiency than their even counterparts, with the even ones most often exhibiting no detectable SH signal. Preliminary single crystal X-ray diffraction studies performed on the PNP-twin series showed that while the even members possess a molecular center of symmetry and pack centro-symmetrically, the odd ones do not, leading to the observed alternation. The orientational-disordering dynamics of two of the twin series – the PNP and the Sulfazo-twin series, doped in a poly(methyl methacrylate) matrix, was also studied by monitoring the SH-signal decay in electric field poled samples. Interestingly, the maximum attainable SH signal, χ(2), in the poled samples also showed an odd-even oscillation with the odd ones again exhibiting a higher value of χ(2). The temporal stability of the SHG intensity at 70°C, after the removal of the applied corona, was also studied and the relaxation of the chromophores was found to follow a biexponential decay. The slower relaxation component exhibits a spacer length dependence, which suggests the interplay of two factors in governing the temporal stability in such polymer doped twin systems, one is the conformational discomfort experienced by the spacer in adopting a U-shaped geometry, and the other the electrostatic repulsion when two aligned dipoles lie very close to each other.

Structural versatility of oxalamide-based compounds: a computational study on the isomerization of the oxalamide group and the structural preferences of the polyoxalamides.

The conformational properties of the oxalamide group and crystal structure of several polyoxalamides have been investigated by computational methods. First, a detailed quantum mechanical study of the conformational preferences of N,N'-dimethyloxalamide is reported. Results, which were obtained at the MP2/6-31G(d) level, provide not only the minimum energy conformations but also a description of the energetics and structural changes associated to the isomerization process of the oxalamide group. These quantum mechanical results together with those obtained from additional calculations have been used to develop a set of force-field parameters for the oxalamide group. Molecular mechanics calculations have been performed to test the parameters and to provide new information in terms of energy contributions about the isomerization of the oxalamide group. On the other hand, the new set of parameters has been used to investigate the structural preferences of polyoxalamides (-[NH-CO-CO-NH-(CH(2))(n)]-) by PCSP calculations. Results indicated that polyoxalamides with an even number of methylene groups adopt a structure with one hydrogen bonding direction, whereas polymers with an odd number of methylene groups prefer a structure with two hydrogen bonding directions. The latter crystal structure is completely different from that observed in conventional polyamides and has been investigated in detail through Monte Carlo simulations.

Antioxidative and 5-lipoxygenase inhibiting activities of novel bis(4-hydroxy-2,3,5-trimethylphenoxy)alkyl derivatives.

Novel bis(4-hydroxy-2,3,5-trimethylphenoxy)alkyl derivatives were synthesized and evaluations were made of their inhibiting action on Fe3+-ADP induced lipid peroxidation in rat liver microsome and reducing action on alpha,alpha-diphenyl-beta-picrilhydrazyl (DPPH), a stable radical, in addition to their inhibiting action on 5-lipoxygenase (5-LO), an enzyme that synthesizes leukotrienes. We performed a structure-activity correlation study on these derivatives. A strong Fe3+-ADP induced lipid peroxidation preventing activity was observed for the derivatives with an odd number of methylene groups including 1,3-bis(4-hydroxy-2,3,5-trimethylphenoxy)propane (3b) and 3a. No change in the DPPH reducing activity was found with change in the number of methylene groups. 5-LO inhibiting activity among the derivatives was the highest for 1,6-bis(4-hydroxy-2,3,5-trimethylphenoxy)hexane (3e). MM2 calculations were performed to find a stable steric structure for the derivatives, and 1,5-bis(4-hydroxy-2,3,5-trimethylphenoxy)pentane (3d) showed a strong activity in both antioxidative action and 5-LO inhibiting action.

Diacetylene polymerization in self-assembled monolayers: influence of the odd/even nature of the methylene spacer

In this study, the interdependence between molecular architecture and photo-polymerization is evaluated for self-assembled monolayers containing diacetylenes. While such assemblies provide added robustness and versatility in molecular design, direct surface-attachment significantly limits the degrees of freedom within the monolayer structure. As a result, the polymer conjugation length as evidenced by the chromatic properties cannot be directly predicted from the extensive literature on Langmuir–Blodgett (LB) films. Indeed, a clear odd/even effect is observed in the polymerization properties of these surface-confined monolayers that is not evident in LB systems. Odd-numbered methylene spacers between the surface and the polymer backbone lead to the longer conjugation length blue form, whereas even-numbered spacers yield the shorter conjugation length red phase. This observation is consistent with simple modeling that indicates a release in localized strain upon polymerization for the odd-numbered spacer architectures. While spacers of both 5 and 9 methylene unit yield similar conversion efficiency to the blue-phase polymer, the kinetic profiles with UV exposure are quite different. The longer conversion times for the shorter spacer are attributed to lower freedom of movement within the monolayer to achieve the spatial alignment required for the topochemical polymerization.

Phase Identification in a Series of Liquid Crystalline TPP Polyethers and Copolyethers Having Highly Ordered Mesophase Structures. 8. Phase and Structural Evolution in a Series of Copolyethers Containing Odd-Numbered Methylene Units in Both Comonomers

A series of liquid crystalline copolyethers have been synthesized from 1-(4-hydroxy-4‘-biphenyl)-2-(4-hydroxyphenyl)propane with 1,7-dibromoheptane and 1,11-dibromoundecane (coTPPs-7/11). This represents the copolyethers containing only odd numbers of methylene units in both comonomers. The molar ratio between these two comonomers in this series ranges from 1/9 to 9/1. The coTPPs-7/11 exhibit multiple phase transitions during cooling and heating in differential scanning calorimetry experiments. In each of these thermal transitions, only a small undercooling and superheating dependence is observed upon cooling and heating at different rates. All of the coTPPs-7/11 possess similar phase behavior based on the structural analyses using wide-angle X-ray diffraction (WAXD) on both powder and fiber samples and electron diffraction experiments on thin-film samples in transmission electron microscopy. The low-temperature phase is identified as a tilted hexagonal columnar (ΦTH) phase with multiple tilt angles between molecular axes and the hexagonal lattice normal. However, the hexagonal lateral dimensions in a ΦTH phase with various tilt angles are identical. This ΦTH phase transforms to another columnar (Φ‘) phase during heating at approximately 140 °C, as evidenced by the temperature-resolved WAXD fiber patterns. In this transition, the laterally ordered reflections from the (110) and (200) planes in the quadrants move toward the equator, corresponding to the decreased tilt angles. The discontinuous change in both the lateral d spacings and tilt angles represents a first-order transition. The columnar−columnar phase transition may be associated with the conformational disorder of the methylene units according to the infrared spectroscopic observations. Further heating of the samples leads to transitions from the Φ‘ to a nematic (N) phase and from the N phase to the isotropic melt. Combining the copolymer phase behaviors observed with the corresponding homopolymers TPPs(n = 7 and 11), a phase diagram describing transition temperatures with respect to the composition can be constructed. Their transition properties are also discussed.

Phase Identification in a Series of Liquid Crystalline TPP Polyethers and Copolyethers Having Highly Ordered Mesophase Structures. 6. Structure Changes from Smectic to Columnar Phases in a Series of Copolyethers Containing Odd and Even Numbers of Methylene Units in Equal Molar Composition

A series of liquid crystalline copolyethers has been synthesized from 1-(4-hydroxy-4‘-biphenyl)-2-(4-hydroxyphenyl)propane and different α,ω-dibromoalkanes [coTPP(n/m)]. In this report, coTPPs having n = 5, 7, 9, 11 and m = 12 are studied, which represent copolyethers having both varying odd number and a fixed even number of methylene units. The compositions were fixed at an equal molar ratio (50/50). These coTPPs(n/m) show multiple phase transitions during cooling and heating in differential scanning calorimetry experiments. The undercooling dependence of these transitions is found to be small, indicating that these transitions are close to equilibrium. Although the coTPPs possess a high-temperature nematic (N) phase, the periodicity order along the chain direction is increasingly disturbed when the length of the odd-numbered methylene units decreases from n = 11 to 5. In the coTPPs(5/12, 7/12, and 9/12), wide-angle X-ray diffraction experiments at different temperatures show that, shortly after the N phase formation during cooling, the lateral molecular packing improves toward a hexagonal lattice, as evidenced by a gradual narrowing of the scattering halo. This process represents the possible existence of an exotic N phase, which serves as a precursor to the columnar (ΦH) phase. A further decrease in temperature leads to a ΦH phase having a long-range ordered, two-dimensional hexagonal lattice. In coTPP(11/12), the phase structures are categorized as highly ordered and tilted, smectic and smectic crystal phases, similar to homoTPPs, such as the smectic F (SF) and smectic crystal G (SCG) phases. An interesting observation is found for coTPP(9/12), wherein a structural change from the high-temperature ΦH phase to the low-temperature SF phase occurs. It can be proven that, upon heating, the well-defined layer structure disappears and the lateral packing remains hexagonal. The overall structural differences in this series of coTPPs between those of the columnar and highly ordered smectic phases are related to the disorders introduced into the layer structure by the dissimilarity of the methylene unit lengths in the comonomers.

Phase Transitions of Dimeric Liquid Crystals Containing Long Odd-Numbered Methylene Spacers

A series of α,ω-bis{4-(4-biphenyloxycarbonyl)phenyl} alkanedioates (BPA-n) dimeric liquid crystals having long odd-numbered methylene spacers was prepared. The number of methylene groups in the flexible alkyl spacer has been varied from 9 to 21. Long period L of crystalline BPA-n obtained by X-ray powder diffraction were shown as a linear equation of the number n of methylene units, as follows, L=1.16n+35.2 (Å). BPA-21 showed no liquid crystalline phase. BPA-19 is monotropic nematic. The other BPA-n showed an enantiotropic nematic phase. The overall entropies ΔSKI of the transition from the crystals at room temperature to the isotropic liquid were also shown as a linear equation of n, as follows, ΔSKI=8.54n+94.8 (J K−1 mol−1). The crystal-nematic (TKN) transition temperature shows a weak odd–even oscillation, but the nematic-isotropic (TNI) transition temperature showed a distinctive odd–even effect. The odd–even effect of a TNI decreases with an increase in n. The nematic–isotropic (ΔSNI) entropy change is almost constant with an increase in n with a strong odd–even oscillation, higher values being detected for the homologues with even-numbered spacers.

High-pressure synthesis and properties of aliphatic-aromatic polyimides via nylon-salt-type monomers derived from aliphatic diamines and benzophenonetetracarboxylic acid

Aliphatic polyimides (P-XBTA) having inherent viscosities of 0.4–1.4 dL/g were readily synthesized by the high-pressure polycondensation of the salt monomers, composed of aliphatic diamines having various methylene chain lengths (X = 4–12) and 3,3′,4,4′-benzophenonetetracarboxylic acid (BTA), under 200–250 MPa at 200–320°C. The salt monomers with odd-numbered methylene units were found to be more susceptible to crosslinking than those containing even-numbered methylene chains. The polyimides having even-numbered methylene units were highly crystalline, whereas those with odd-numbered methylene chains were crosslinked and therefore amorphous with only one exception, i.e., P-11BTA. The thermal behavior of these polymers was also studied. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 39–47, 1998

Induced Smectic A and C Phases Formed by Binary Systems of Main-Chain Polymeric and Twin Nematics

The thermal and liquid crystalline properties of the new binary systems, consisting of a polycarbonate type of a main-chain liquid crystal polymer (PC) and a twin liquid crystal (TN-n: n = number of central methylene units) with a nitro terminal unit, were examined. The binary systems having PC and TN-n with even-numbered central methylene units (n = 6, 8) showed an induced smectic A phase with batonnets and a fan texture. However, the binary systems consisting of PC and TN-n with odd-numbered central methylene units (n = 5, 7) formed an induced smectic C phase in addition to an induced smectic A phase. In the induced smectic C phase, the schlieren with two and four brushes was observed.