Linear Side Chains Research Articles

Side-chain engineering for regulating structure and properties of a novel visible-light-driven perylene diimide-based supramolecular photocatalyst

Systematic and in-depth explorations of the effects of side-chain modulation on the molecular assembly, optoelectronic properties, and photocatalytic properties of supramolecular systems, as well as the kinetics of charge separation and migration in these systems, are rare. In this study, a novel supramolecular photocatalyst with an alkoxy side chain (S-EPDI) was successfully developed through subtle design of the short and linear alkoxyl side chains, affording a phenol degradation efficiency approximately four times that of the counterpart with an alkyl side chain (S-APDI). Notably, combined density functional theory (DFT) calculations, absorption spectroscopy, and other characterizations revealed that the perylene diimide (PDI) molecular units, through π-π stacking, formed a unique rotationally offset stacked supramolecular structure, exhibiting a significant dipole moment. This gave rise to the formation of a larger inherent electric field within S-EPDI compared to S-APDI. Moreover, the study quantitatively demonstrated that a stronger inherent electric field and lower rate of surface charge recombination facilitate efficient separation of the photogenerated carriers. Therefore, the side-chain molecular engineering method employed in this study offers an effective approach for modulating the kinetics of charge migration.

Synergistically manipulating the shape of alkyl-chain and asymmetric side groups of non-fullerene acceptors enables organic solar cells to reach 18.5% efficiency

Side-chain modification and asymmetric design for non-fullerene acceptors (NFAs) have been proven to be effective methods for harvesting high-performance organic solar cells (OSCs). Combining the two molecular design strategies, we adopted phenyl chain and alkyl chains with different shapes to develop two novel asymmetric NFAs, named BTP-P2EHC11 and BTP-P2EHC2C4. Compared with BTP-P2EHC2C4 attached 2-ethylhexyl side chain, BTP-P2EHC11 with linear alkyl side chain have slightly red-shifted absorption and intensive absorption strength. Moreover, the PM6:BTP-P2EHC11 blend film presents higher and more balanced charge mobilities, reducing charge recombination, tighter intermolecular packing and more favorable fibrous network morphology with appropriate phase separation than PM6:BTP-P2EHC2C4, which lead to significantly enhanced short-circuit current density (JSC) of PM6:BTP-P2EHC11-based devices. Thus, the OSCs based on PM6:BTP-P2EHC11 achieve a superior power conversion efficiency (PCE) of 18.50% with a good trade-off among open-circuit voltage (VOC) of 0.876 V, JSC of 26.85 mA cm−2 and fill factor (FF) of 78.65%, while PM6:BTP-P2EHC2C4-based device exhibits a lower PCE of 17.49%. Our investigation elucidates that the combination of finely optimizing the shape of alkyl-chain and asymmetric side groups of NFAs could pave a promising avenue toward morphology optimization and performance promotion of OSCs.

The Discovery of Acremochlorins O-R from an Acremonium sp. through Integrated Genomic and Molecular Networking.

The fermentation of a soil-derived fungus Acremonium sp. led to the isolation of thirteen ascochlorin congeners through integrated genomic and Global Natural Product Social (GNPS) molecular networking. Among the isolated compounds, we identified two unusual bicyclic types, acremochlorins O (1) and P (2), as well as two linear types, acremochlorin Q (3) and R (4). Compounds 1 and 2 contain an unusual benzopyran moiety and are diastereoisomers of each other, the first reported for the ascochlorins. Additionally, we elucidated the structure of 5, a 4-chloro-5-methylbenzene-1,3-diol with a linear farnesyl side chain, and confirmed the presence of eight known ascochlorin analogs (6-13). The structures were determined by the detailed interpretation of 1D and 2D NMR spectroscopy, MS, and ECD calculations. Compounds 3 and 9 showed potent antibacterial activity against Staphylococcus aureus and Bacillus cereus, with MIC values ranging from 2 to 16 μg/mL.

Reticular liquid crystal design: Controlling complex self-assembly of p-terphenyl rods by side-chain engineering and chirality

A series of K-shaped bolapolyphiles, consisting of a p-terphenyl core, two polar glycerol end-groups and a swallow-tailed alkyl side-chain were synthesized and investigated. By increasing the side-chain volume an astonishing variety of very different liquid crystalline (LC) phases was observed, ranging from a rectangular (Colrec/c2mm) and a square honeycomb (Colsqu/p4mm) via a highly complex zeolite-like octagon/pentagon honeycomb filled with additional strings of rod-bundles (ColrecZ/c2mm), a new 3D-hexagonal (R3‾c) double network phase, a double and even a single network cubic phase (double gyroid Cub/Ia3‾d and single diamond Cub/Fd3‾m, respectively) to a correlated lamellar phase (LamSm/c2mm). Though these LC structures are highly complex and there is a delicate balance of steric and geometric frustration determining the phase formation, there is only a small effect of permanent molecular chirality in the glycerol groups ((R,R)-configuration) on them, which is attributed to a slightly different packing density of uniformly chiral and racemic glycerols, but not to an effect of induced helicity. Compared to related T-shaped bolapolyphiles with a single linear n-alkyl side-chain, which form exclusively honeycomb phases, the complexity of self-assembly is enhanced for the K-shaped compounds due to a competition between the requirements of space filling, chain stretching and geometric frustration, and affected by the shape of the polar glycerol domains at the junctions.

Suppress energy loss to boost power conversion efficiency of organic photovoltaics with linear side chains modulation

The high energy loss (Eloss) in organic solar cells (OSCs) is being the one of major problem, which limit the power conversion efficiency (PCE) of OSCs. In this work, we designed and synthesized three perylene diimide (PDI)-based Acceptor’-Donor-Acceptor-Donor- Acceptor’ (A′-DAD-A′) small molecules namely anti-PDFC-Cx (C8, C10, and C12) by changing the length of linear chains on IDT cores to investigate how the length of linear side chain affects Eloss and the power conversion efficiencies (PCEs) of OSCs. The optical energy bandgap and stacking mode for three anti-PDFC-Cx (C8, C10, and C12) remain the same, which were not influenced by the different lengths of side chains. Increasing the length of side chains on IDT cores from C8 to C10 and C12 would improve the PCE of PM6: anti-PDFC-Cx based devices from 11.52% to 12.43% and 12.27%, particularly the Voc increasing from 0.98 V of anti-PDFC-C8 and 1.00 V of anti-PDFC-C10 to 1.02 V of anti-PDFC-C12. Eloss analysis indicated the value of Eloss reduced as the length increases from C8, to C12. These results demonstate linear side chain engineer is an effective method to reduce Eloss and realize high PCE on the bases of not modulating the stacking mode of acceptor.

Linear versus Helical Side Chains in Bottlebrush Polymers: Morphology and Mechanochemistry

Linear versus Helical Side Chains in Bottlebrush Polymers: Morphology and Mechanochemistry

The role of monomer geometry on the properties of polyolefins: A numerical study

AbstractWe explore the role of monomer geometry on the structural, dynamic, and thermodynamic properties of polyolefis by employing all‐atom molecular dynamic simulations. Specifically, we compare properties of atactic polyolefins in the molten state including polypropylene (aPP), a short‐chain branched polymer: poy(1‐hexene) (aPH), and a polymer having cyclic olefins: poly(vinyl cyclobutane) (aPVCB). We find polymers having the same chain mass and atom composition (hydrocarbon‐based molecules), but having different monomer architecture differ strongly in material properties. In particular, the polymer glass transition () and bulk modulus () show higher values for aPVCB in comparison to aPP and aPH. This increase is caused by having the carbon atoms in a cyclic structure, making aPVCB achieve higher mass and energy densities. By contrast, adding linear short side chains to polymer backbones causes a reduction in and , since side chains make backbones displace each other reducing their packing and thus their mass and energy densities. More broadly, our numerical results suggest that the incorporation of VCB monomers to linear polyolefins will enhance their properties, opening the possibility for designing a new set of materials.

Discovery of a polyketide carboxylate phytotoxin from a polyketide glycoside hybrid by β-glucosidase mediated ester bond hydrolysis.

Fungal phytotoxins cause significant harm to agricultural production or lead to plant diseases. Discovering new phytotoxins, dissecting their formation mechanism and understanding their action mode are important for controlling the harmful effects of fungal phytopathogens. In this study, a long-term unsolved cluster (polyketide synthase 16, PKS16 cluster) from Fusarium species was thoroughly investigated and a series of new metabolites including both complex α-pyrone-polyketide glycosides and simple polyketide carboxylates were identified from F. proliferatum. The whole pathway reveals an unusual assembly and inactivation process for phytotoxin biosynthesis, with key points as follows: (1) a flavin dependent monooxygenase catalyzes Baeyer-Villiger oxidation on the linear polyketide side chain of α-pyrone-polyketide glycoside 8 to form ester bond compound 1; (2) a β-glucosidase unexpectedly mediates the ester bond hydrolysis of 1 to generate polyketide carboxylate phytotoxin 2; (3) oxidation occurring on the terminal inert carbons of 2 by intracellular oxidase(s) eliminates its phytotoxicity. Our work identifies the chemical basis of the PKS16 cluster in phytotoxicity, shows that polyketide carboxylate is a new structural type of phytotoxin in Fusarium and importantly uncovers a rare ester bond hydrolysis function of β-glucosidase family enzymes.

(Invited) Interface Engineering for Organic and Perovskite Photovoltaics

Organic and perovskite solar cells have been intensively studied because they are considered as one of the most promising photovoltaic devices. Indeed, power conversion efficiencies (PCEs) have recently exceeded 19% for organic solar cells and 25% for perovskite solar cells. In both devices, interface engineering is highly important for efficient photovoltaic performance. In particular, it has great impact on open-circuit voltage (V OC) because charge carriers would recombine bimolecularly at the interface. In this talk, I will discuss how interface impact on V OC in polymer solar cells and perovskite solar cells.First, I will discuss how interfacial charge transfer (CT) states impact on V OC in polymer solar cells. More specifically, we employed two crystalline polymers (PTzBT-BOHD and PTzBT-12OD) and a fullerene derivative (PCBM). PTzBT-BOHD and PTzBT-12OD consist of the same backbone with different side chains: PTzBT-BOHD has two branched side chains of butyloctyl (BO) and hexyldecyl (HD) groups and PTzBT-12OD has a linear side chain of dodecyl (12) group and a branched side chain of octadecyl (OD) group. Interestingly, these PTzBT-BOHD/PCBM and PTzBT-12OD/PCBM solar cells exhibited different V OCs, although the two crystalline polymer neat films exhibit the same ionization energy because of the same backbone structure. In order to address the origin of the different V OCs, we carefully analyzed the interfacial CT state in the blend films. As a result, we found the interfacial CT state energy is higher in PTzBT-BOHD/PCBM than in PTzBT-12OD/PCBM blend films. This is because HOMO level of PTzBT-BOHD is deeper than that of PTzBT-12OD in disordered mixed phase in blend films, which results from twisted backbone of PTzBT-BOHD with branched side chains [1].Next, I will discuss how aging and passivation impact on interfacial energy matching and hence V OC in perovskite solar cells. As reported previously, V OC is often improved by ambient storage, which is called aging effect, and also improved by addition of passivation layers, which is called passivation effect. Such improvements in V OC suggest recombination would be suppressed effectively in these devices. Interestingly, V OC was gradually improved during ambient storage even for the passivated device where surface recombination is effectively suppressed by the passivation layer. By analyzing electronic properties of each layer, we found that no change was observed for the perovskite layer but the HOMO level deepening was observed for a hole-transporting material of spiro-OMeTAD during the ambient storage. As a result, energy matching between perovskite and spiro-OMeTAD layers was significantly improved and hence surface recombination was further effectively suppressed, resulting in the improvement in V OC [2,3].These findings clearly show that the electronic state at the interface critically impacts on V OC not only in polymer solar cells but also in perovskite solar cells, and therefore suggest that device design based on interface engineering is of particular importance for further improvement in V OC.

Designing high‐performance nonfused ring electron acceptors via side‐chain engineering

AbstractThe side‐chain has a significant influence on the optical properties and aggregation behaviors of the organic small molecule acceptors, which becomes an important strategy to optimize the photovoltaic performance of organic solar cells. In this work, we designed and synthesized three brand‐new nonfused ring electron acceptors (NFREAs) OC4‐4Cl‐Ph, OC4‐4Cl‐Th, and OC4‐4Cl‐C8 with hexylbenzene, hexylthiophene, and octyl side chains on the π‐bridge units. Compared with OC4‐4Cl‐Ph and OC4‐4Cl‐Th, OC4‐4Cl‐C8 with linear alkyl side chain has more red‐shift absorption, which is conducive to obtaining higher short‐circuit current density. Additionally, the OC4‐4Cl‐C8 film exhibits a longer exciton diffusion distance, and the D18:OC4‐4Cl‐C8 blend film displays faster hole transfer, weaker bimolecular recombination, and more efficient exciton transport. Furthermore, The D18:OC4‐4Cl‐C8 blend films may effectively form interpenetrating networks that resemble nanofibrils, which can facilitate exciton dissociation and charge transport. Finally, OC4‐4Cl‐C8‐based devices can be created a marvellously power conversion efficiency (PCE) of 16.56%, which is much higher than OC4‐4Cl‐Ph (12.29%)‐ and OC4‐4Cl‐Th‐based (11.00%) ones, being the highest PCE among the NFREA based binary devices. All in all, we have validated that side‐chain engineering is an efficient way to achieve high‐performance NFREAs.

A comparative study of the effects of gas bubbles generated from hydrazine or/and water on the surface morphology and hydrophobicity of electrodeposited polymer films

The electrodeposition of polymeric films of a fluorene-bridged dicarbazole monomer containing linear polyfluorinated side chains is here investigated, with regard to the use of on-site electrochemically generated gas bubbles from hydrazine or water as soft template agent. The interconnected effects of the bubbles precursor and electrochemical parameters employed on the morphology and water wettability properties of the electrodeposited films are demonstrated. The use of N2H4 as a gas precursor proved to be a versatile, complementary alternative to water, which allows a finer tuning of the electrodeposited polymer film morphology.

Construction of Enantioenriched Quaternary C-Cl Oxindoles through Palladium-Catalyzed Asymmetric Allylic Substitution with Chloroenolates.

A palladium-catalyzed asymmetric chloroenolate allylation with vinyl benzoxazinanones under mild reaction conditions has been developed, affording a series of optically active 3,3-disubstituted oxindoles exhibiting a chloro-group and a linear aryl amino side chain in good yields with up to 96% ee. Versatile functional group tolerance on the benzene ring has been demonstrated, and the utility of this method was probed by a scale-up synthesis and highlighted by product derivatizations.

Manipulating Crystal Stacking by Sidechain Engineering for High‐Performance N‐Type Organic Semiconductors

AbstractY‐series non‐fullerene acceptors (NFAs) have achieved great progress in organic solar cells (OSCs). Most research attention is currently paid to their molecular engineering to improve the efficiency of OSCs. However, as n‐type organic semiconductors, the relationship between their molecular packing structures and charge transport properties is mostly ignored. Herein, it is clarified how the molecular packing of Y‐series NFAs fundamentally determines their charge transport properties by manipulating their crystal stacking via sidechain engineering. Therefore, branched alkyl/alkoxy substitutions are taken on a reference NFA (Y6‐1O), affording three derivatives, namely 1OBO‐1, 1OBO‐2, and 1OBO‐3. Results show that while the replacement of branched alkyl/alkoxy sidechains has little impact on optical properties and energy levels, it can change crystal stacking motifs significantly. The single crystal of Y6‐1O with all linear sidechains forms a 2D‐brickwork structure and shows lower mobility. In contrast, 1OBO‐2 with all branched sidechains exhibits a favorable 3D interpenetrating porous network, displaying an electron mobility of 1.42 cm2 V−1 s−1 in single‐crystal organic field‐effect transistors (SC‐OFETs). This value is among the highest for NFA‐based n‐type OFETs. This study not only reveals the fundamental structure–property relationships of Y‐series NFAs, but also suggests the potential of Y‐series NFAs for high‐performance n‐type organic semiconductors.

The effect of branched versus linear side chain on thieno[3,4-c]pyrrole-4,6-dione-based donor-acceptor-donor type monomers and their p- and n-dopable polymers

The conjugated backbone has been the focus of the most research, while the structure of the side chains has received less attention. Here, we focus on making new donor–acceptor–donor (D–A–D) type conjugated monomers by bearing a thieno[3,4-c]pyrrole-4,6-dione (TPD) with octyl chain at the imide nitrogen as the acceptor unit and 3,4-ethylenedioxythiophene (EDOT), and 3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine (ProDOT) as the donor units and their corresponding polymers. The optical and electrochemical properties of octyl substituted monomers and their corresponding polymers were compared with their ethylhexyl counterparts. Changing the alkyl side chain on the TPD unit from linear to branched has no effect on onset potential, optical band gap (Eg), perceived color, electrochromic contrast, or switching time. Nonetheless, donor strength has significant impact on the properties of monomers and their corresponding polymers. EDOT-bearing monomers and polymers have lower onset and oxidation potentials, Eg values than their ProDOT counterparts due to more electron donating ability of ethylenedioxy bridge in comparison to the propylenedioxy bridge. Octyl substituted monomers, P-Octyl and E-Octyl, demonstrated high sensitivity towards the Fe3+ ion, making them viable candidates for use in ion sensing, and their corresponding polymers, PE-Octyl and PP-Octyl, are both p- and n-dopable, which is a desirable property for conjugated polymers. Furthermore, PP-Octyl was found to be soluble in common solvents, and PP-Octyl in toluene can be oxidized with antimony pentachloride (SbCl5).

Indacenodithienothiophene-based A-D-D′-D-A-type small-molecule donors for all-small-molecule organic solar cells

Research on all-small-molecule organic solar cells (SM-OSCs) is growing due to the advantages of small-molecule donor materials. In this study, we synthesized and characterized two small-molecule donors of A-D-D′-D-A type based on highly fused indacenodithiophene (IDTT), namely BDT-IDTT-ORH and BDT-C8IDTT-ORH. The different side chains of these two molecules, 4-hexylphenyl and n-octyl, led to different crystallinities in the film state. The two synthesized donors exhibited absorption in the long wavelength range of 400–700 nm due to effective π-conjugation caused by their planar structures. Because their absorption bands are complementary to that of the Y6 non-fullerene acceptor, these molecules showed potential as small-molecule donors in donor:Y6 blend for SM-OSCs. In particular, the BDT-C8IDTT-ORH:Y6 blend exhibited the highest power conversion efficiency (PCE) of 6.33%. This higher PCE is due to a relatively higher JSC value for BDT-C8IDTT-ORH with linear n-octyl side chains, thanks to its tighter molecular packing compared to that of BDT-IDTT-ORH with 4-hexylphenyl side chains.

A-DA′D-A Type Acceptor with a Benzoselenadiazole A′-Unit Enables Efficient Organic Solar Cells

A new A-DA′D-A structured narrow bandgap small molecular acceptor (SMA) Se46 was designed and synthesized by using benzoselenadiazole as the A′ unit and branched 2-butyloctyl as upper side chains in its DA′D central fused ring. It was found that Se46 shows red-shifted absorption compared to that of L8-BO with a benzothiadiazole A′ unit and an up-shifted lowest unoccupied molecular orbital energy level compared to that of Y6 with a benzothiadiazole A′ unit and linear n-C11H23 upper side chains. The organic solar cells (OSCs) based on PM6:Se46 demonstrate a high power conversion efficiency over 18% with an increased short circuit current density compared to that of the L8-BO-based devices and a higher open circuit voltage than that of the Y6-based devices. The results indicate that the synergetic modification of selenium substitution in the A′ unit and branched alkyl upper side chain is an effective strategy to further promote photovoltaic performance for the narrow bandgap A-DA′D-A type acceptors.

Hierarchical surface structure and performance of fluorinated copolymer films derived from side chain structure and α-position substitution of fluorinated monomeric units

Low surface energy and low surface reconfiguration are two key properties being sought for fluorinated polymer films with short perfluoroalkyl groups, which are mainly determined by the molecular structure of fluorinated monomers. In this work, six typical C6 fluorinated monomers were selected to synthesize fluorinated polymer nanoparticles (f-PNPs) through miniemulsion polymerization. Fluorinated polymer films were further fabricated through spin-coating by using f-PNPs as the building blocks. Influences of the molecular structure of fluorinated monomers and heat treatment conditions on the surface element composition, arrangement of fluorinated side chains, surface morphology, surface performance, and underwater surface configuration of fluorinated polymer films were systematically investigated. The results showed both the fluorinated side chain structure and α-position substitution of fluorinated monomeric units played a significant role in the surface F enrichment extent, organized arrangement of fluorinated side chains at the surface, surface morphology, and finally the surface free energy. Generally, fluorinated polymer films with linear fluorinated side chains ended with –CF3 displayed stable low surface energy and low surface reorganization attributed to forming relatively organized packing structures of fluorinated side chains. This study contributes to providing a guide to design and fabricating low surface free energy nanomaterials or films with perfluoroalkyl (meth)acrylate copolymers bearing short perfluoroalkyl groups.

COAP‐Palladium‐Catalyzed Asymmetric Linear Allylic Alkylation of Vinyl Benzoxazinanones for Multifunctional 3,3′‐Disubstituted Oxindole Derivatives

AbstractA Pd‐catalyzed enantioselective linear‐allylic alkylation of vinyl benzoxazinanones with a series of 3‐substituted oxindoles was reported in the presence of a chiral oxamide‐phosphine ligand (COAP−Bn) under mild reaction conditions. A series of optically active multifunctional 3,3′‐disubstituted oxindole derivatives bearing a quaternary stereogenic center and a linear aryl amino side chain were respectively obtained in 55–98% yields with 96–99% ee for 3‐(hetero)aryl substituted oxindoles. The developed protocol demonstrates that the COAP ligands could serve as a privileged chiral ligand to construct diverse chiral 3,3‐disubstituted oxindole compounds with various quaternary stereogenic centers, such as aza‐, thio‐ or all‐carbon quaternary stereogenic centers. The salient features of the method include broad substrate scope, N‐protecting group free, base‐free, and high regio‐ and enantioselectivity.magnified image

Oligo(ethylene glycol) Side Chain Architecture Enables Alcohol-Processable Conjugated Polymers for Organic Solar Cells

Achieving green-solvent solubility of conjugated polymers in truly green solvents such as alcohols has proven to be a significant challenge. In this work, we report the synthesis and characterization of three conjugated polymers derived from poly[(thiophene)-alt-(6,7-difluoro-2-(2-hexyldecyloxy)quinoxaline)] (PTQ10) with the goal of developing derivates which are more green-solvent-processable. The traditional alkyl side chains are replaced by various oligo(ethylene glycol) (OEG) side chains of different architectures, including one linear and two branched, all of which contain six ethylene glycol repeating units. It is determined that the linear OEG side chain architecture, even when sufficiently long, will not give desired green-solvent solubility shown by a small solubility capacity (R0). However, branched OEG side chains significantly improve solubility as R0 was increased from 4.7 of PTQ10 to 11.9 of PTQ-6bO/6bO2. Although the solution states of the polymers were vastly different, the solid-state morphologies were more similar as all three OEG-based polymers retained a predominately face-on molecular orientation similar to PTQ10. It was demonstrated that PTQ-6O devices showed the most comparable power conversion efficiencies (PCEs) to PTQ10 in bulk heterojunction solar cells, while PTQ-6bO2 and PTQ-6bO showed poorer performances. With one extra carbon in the side chain, PTQ-6bO2 showed higher PCE than PTQ-6bO, attributed to the improved aggregation properties and solid-state morphology of PTQ-6bO2, highlighting the importance of OEG side chain architecture. This work serves to develop important guidelines for future alcohol-soluble materials for green-solvent-processed OPVs.

Structure-activity relationship study of antitrypanosomal analogues of gibbilimbol B using multivariate analysis and computation-aided drug design

Gibbilimbol B and analogues were isolated from the Brazilian plant Piper malacophyllum and displayed activity against trypomastigote forms of Trypanosoma cruzi as well as reduced toxicity against NCTC cells. These results stimulated the preparation of a series of 24 chemically related analogues to study the potential of these compounds against T. cruzi trypomastigotes and explore structure–activity relationships. Initially, 12 compounds were planned, maintaining the same extension of the linear side chain of gibbilimbol B and unsaturation on the C-4 position but changing the functional groups – ester and amide – and variating the substituent at the p-position in the aromatic ring. Other 12 compounds were prepared using a branched side chain containing an ethyl group at the C-2 position. Overall, these structurally-related analogues demonstrated promising activity against trypomastigote forms (EC50 < 20 μM) and no mammalian cytotoxicity to fibroblasts (CC50 > 200 μM). Using multivariate statistics and machine learning analysis, aspects associated with structure/activity were related to their three-dimensional structure and, mainly, to the substituents on the aromatic ring. Obtained results suggested that the presence of t-butyl or nitro groups at p-position with appropriate side chains causes an alteration in the electron topological state, Van der Waals volumes, surface areas, and polarizabilities of tested compounds which seem to be essential for biological activity against T. cruzi parasites.