RESUMO
Red beetroot extract (E162) is a natural colorant that owes its color to betanin, its major red pigment. Betanin displays remarkable antioxidant, anti-inflammatory, and chemoprotective properties mediated by its structure and influence on gene expression. However, the betanin employed in most preclinical assays is a beetroot extract diluted in dextrin, not pure betanin, as no isolated compound is commercially available. This makes its use inaccurate concerning product content estimates and biological effect assessments. Herein, a combination of conventional extraction under orbital shaking and ultrasound-assisted extraction (UAE) to purify betanin by semi-preparative HPLC was performed. The employed methodology extracts betalains at over a 90% yield, achieving 1.74 ± 0.01 mg of pure betanin/g beetroot, a 41% yield from beetroot contents increasing to 50 %, considering the betalains pool. The purified betanin exhibited an 85% purity degree against 32 or 72% of a commercial standard evaluated by LC-MS or HPLC methods, respectively. The identity of purified betanin was confirmed by UV-Vis, LC-MS, and 1H NMR. The combination of a conventional extraction, UAE, and semi-preparative HPLC allowed for betanin purification with a high yield, superior purity, and almost three times more antioxidant power compared to commercial betanin, being, therefore, more suitable for clinical purposes.
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Biopolymers obtained from natural macromolecules are noteworthy among materials presenting high biocompatibility and adequate biodegradability, as is the case of chitosan (CS), making this biopolymeric compound a suitable drug delivery system. Herein, chemically-modified CS were synthetized using 2,3-dichloro-1,4-naphthoquinone (1,4-NQ) and the sodium salt of 1,2-naphthoquinone-4-sulfonic acid (1,2-NQ), producing 1,4-NQ-CS and 1,2-NQ-CS by three different methods, employing an ethanol and water mixture (EtOH:H2O), EtOH:H2O plus triethylamine and dimethylformamide. The highest substitution degree (SD) of 0.12 was achieved using water/ethanol and triethylamine as the base for 1,4-NQ-CS and 0.54 for 1,2-NQ-CS. All synthesized products were characterized by FTIR, elemental analysis, SEM, TGA, DSC, Raman, and solid-state NMR, confirming the CS modification with 1,4-NQ and 1,2-NQ. Chitosan grafting to 1,4-NQ displayed superior antimicrobial activities against Staphylococcus aureus and Staphylococcus epidermidis associated with improved cytotoxicity and efficacy, indicated by high therapeutic indices, ensuring safe application to human tissue. Although 1,4-NQ-CS inhibited the growth of human mammary adenocarcinoma cells (MDA-MB-231), it is accompanied by cytotoxicity and should be considered with caution. The findings reported herein emphasize that 1,4-NQ-grafted CS may be useful in protecting injured tissue against bacteria, commonly found in skin infections, until complete tissue recovery.
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Leishmaniasis is a highly prevalent, yet neglected disease caused by protozoan parasites of the genus Leishmania. In the search for newer, safer, and more effective antileishmanial compounds, we herein present a study of the mode of action in addition to a detailed structural and biological characterization of LQOF-G6 [N-benzoyl-N'-benzyl-Nâ³-(4-tertbutylphenyl)guanidine]. X-ray crystallography and extensive NMR experiments revealed that LQOF-G6 nearly exclusively adopts the Z conformation stabilized by an intramolecular hydrogen bond. The investigated guanidine showed selective inhibitory activity on Leishmania major cysteine protease LmCPB2.8ΔCTE (CPB) with ~73% inhibition and an IC50-CPB of 6.0 µM. This compound did not show any activity against the mammalian homologues cathepsin L and B. LQOF-G6 has been found to be nontoxic toward both organs and several cell lines, and no signs of hepatotoxicity or nephrotoxicity were observed from the analysis of biochemical clinical plasma markers in the treated mice. Docking simulations and experimental NMR measurements showed a clear contribution of the conformational parameters to the strength of the binding in the active site of the enzyme, and thus fit the differences in the inhibition values of LQOF-G6 compared to the other guanidines. Furthermore, the resulting data render LQOF-G6 suitable for further development as an antileishmanial drug.
Assuntos
Cisteína Proteases , Leishmania major , Leishmaniose , Animais , Camundongos , Cisteína Proteases/metabolismo , Guanidina , Virulência , Leishmaniose/tratamento farmacológico , Mamíferos/metabolismoRESUMO
Among the compounds of natural origin, diterpenes have proved useful as drugs for the treatment of cancer. Marine organisms, such as soft corals and algae, are a promising source of diterpenes, being a rich and unexplored source of cytotoxic agents. This study evaluated a library of 32 natural and semisynthetic marine diterpenes, including briarane, cembrane, and dolabellane nuclei, with the aim of determining their cytotoxicity against three human cancer cell lines (A549, MCF7, and PC3). The three most active compounds were submitted to a flow cytometry analysis in order to determine induction of apoptosis against the A549 cell line. An NMR analysis was conducted to determine and evaluate the interactions between active diterpenes and tubulin. These interactions were characterized by a computational study using molecular docking and MD simulations. With these results, two cembrane and one chlorinated briarane diterpenes were active against the three human cancer cell lines, induced apoptosis in the A549 cell line, and showed interactions with tubulin preferably at the taxane-binding site. This study is a starting point for the identification and optimization of the marine diterpenes selected for better antitumor activities. It also highlights the power of integrating NMR studies, computational predictions, and in vitro assays in the search for compounds with antitumor activity.
Assuntos
Antozoários/química , Antineoplásicos/química , Produtos Biológicos/química , Misturas Complexas/química , Diterpenos/química , Bibliotecas de Moléculas Pequenas/química , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Misturas Complexas/farmacologia , Biologia Computacional , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Halogenação , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-AtividadeRESUMO
Lisdexamfetamine dimesylate (LDX), a long-acting prodrug stimulant indicated for the treatment of the attention-deficit/hyperactivity disorder (ADHD), was subjected to forced degradation studies by acid and alkaline hydrolysis and the degradation profile was studied. To obtain between 10-30% of degraded product, acid and alkaline conditions were assessed with solutions of 0.01 M, 0.1 M, 0.5 M, and 1 M of DCl and NaOD. These solutions were analyzed through 1 H NMR spectra. Acid hydrolysis produced no degradation in 0.01 M and 0.1 M DCl and 4.38%, 9.69%, and 17.75% of degradation LDX, respectively, in 0.5 M, 1 M (4h) and 1 M (4 + 12 h) DCl. And alkaline hydrolysis produced no degradation in 0.01 M and 0.1 M DCl and a degradation LDX extension of 8.5%, 14.30%, and 22.91%, respectively, in 0.5 M, 1 M (4h) and 1 M (4 + 12 h) NaOD. LDX solutions subjected to 1 M (4 + 12 h) acid and alkaline hydrolysis were evaluated by NMR spectra (1 H NMR, 13 C NMR, HSQC and HMBC). LDX degradation product (DP) was identified and its structure elucidated as a diastereoisomer of LDX: (2R)-2,6-diamino-N-[(2S)-1-phenylpropan-2-yl] hexanamide without their physical separation.
Assuntos
Estimulantes do Sistema Nervoso Central/análise , Estimulantes do Sistema Nervoso Central/metabolismo , Dimesilato de Lisdexanfetamina/análise , Dimesilato de Lisdexanfetamina/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Estabilidade de MedicamentosRESUMO
Herein, we report the synthesis and mass spectrometry studies of several N-alkylbenzenesulfonamides structurally related to sulfanilic acid. The compounds were synthesized using a modified Schotten-Baumann reaction coupled with Meisenheimer arylation. Sequential mass spectrometry by negative mode electrospray ionization (ESI(-)-MS/MS) showed the formation of sulfoxylate anion (m/z 65) observed in the mass spectrum of p-chloro-N-alkylbenzenesulfonamides. Investigation of the unexpected loss of two water molecules, as observed by electron ionization mass spectrometry (EI-MS) analysis of p-(N-alkyl)lactam sulfonamides, led to the proposal of corresponding fragmentation pathways. These compounds showed loss of neutral iminosulfane dioxide molecule (M-79) with formation of ions observed at m/z 344 and 377. These ions were formed by rearrangement on ESI(+)-MS/MS analysis. Some of the molecules showed antagonistic activity against Kv3.1 voltage-gated potassium channels.
Assuntos
Antibacterianos/química , Bloqueadores dos Canais de Potássio/química , Canais de Potássio Shaw/efeitos dos fármacos , Ácidos Sulfanílicos/química , Sulfonamidas/química , Antibacterianos/síntese química , Desenho de Fármacos , Espectrometria de Massas por Ionização por Electrospray , Sulfonamidas/síntese química , Espectrometria de Massas em TandemRESUMO
New N-p-chloro-, N-p-bromo-, and N-p-nitrophenylazobenzylchitosan derivatives, as well as the corresponding azophenyl and azophenyl-p-sulfonic acids, were synthesized by coupling N-benzylvchitosan with aryl diazonium salts. The synthesized molecules were analyzed by UV-Vis, FT-IR, 1H-NMR and 15N-NMR spectroscopy. The capacity of copper chelation by these materials was studied by AAS. Chitosan and the derivatives were subjected to hydrolysis and the products were analyzed by ESI(+)-MS and GC-MS, confirming the formation of N-benzyl chitosan. Furthermore, the MS results indicate that a nucleophilic aromatic substitution (SnAr) reaction occurs under hydrolysis conditions, yielding chloroaniline from N-p-bromo-, and N-p-nitrophenylazo-benzylchitosan as well as bromoaniline from N-p-chloro-, and N-p-nitrophenylazobenzyl-chitosan.
Assuntos
Quitosana/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrólise , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodosRESUMO
This work deals with the spectroscopic (supported by quantum chemistry calculations), structural, and morphological characterization of mefenamic acid (2-[(2,3-(dimethylphenyl)amino] benzoic acid) polymorphs, known as forms I and II. Polymorph I was obtained by recrystallization in ethanol, while form II was reached by heating form I up to 175 °C, to promote the solid phase transition. Experimental and theoretical vibrational band assignments were performed considering the presence of centrosymmetric dimers. Besides band shifts in the 3345-3310 cm(-1) range, important vibrational modes to distinguish the polymorphs are related to out-of-phase and in-phase N-H bending at 1582 (Raman)/1577 (IR) cm(-1) and 1575 (Raman)/1568 (IR) cm(-1) for forms I and II, respectively. In IR spectra, bands assigned to N-H bending out of plane are observed at 626 and 575 cm(-1) for polymorphs I and II, respectively. Solid-state (13)C NMR spectra pointed out distinct chemical shifts for the dimethylphenyl group: 135.8 to 127.6 ppm (carbon bonded to N) and 139.4 to 143.3 ppm (carbon bonded to methyl group) for forms I and II, respectively.
Assuntos
Anti-Inflamatórios não Esteroides/química , Ácido Mefenâmico/química , Simulação por Computador , Cristalização , Etanol/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Modelos Químicos , Estrutura Molecular , Transição de Fase , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Temperatura , Vibração , Difração de Raios XRESUMO
OBJECTIVE: To measure infants' breast milk intake and infant growth when their mothers initiated either combined oral contraceptive (COC), levonorgestrel-releasing intrauterine system, or etonogestrel-releasing implant, or copper intrauterine device (IUD) as a reference group. DESIGN: Prospective trial. SETTING: University-based hospital. PATIENT(S): On postpartum day 42, 40 women initiated a contraceptive method according to their choice. INTERVENTION(S): Deuterium (D2O; 0.5 g/kg mother's weight) was ingested by mothers on postpartum days 42, 52, and 63 as a marker of total body fluid. MAIN OUTCOME MEASURE(S): Infants' milk intake from 42 to 63 postpartum days was assessed by measurement of D2O levels in infants' saliva and infant growth by measuring their body weight, height, and tibia length. Women recorded all infant feed and changes of diapers wet with urine. Breastfeeding continuation was assessed at 6 months postpartum. RESULT(S): Infant mean milk intake, mean growth increase, mean number of breastfeeding episodes, daily wet diaper changes, and mean duration of exclusively breastfeeding (~5 months) were similar in the four groups. CONCLUSION(S): Use of a COC, the two progestin-only contraceptives, or copper IUD did not affect the amount of infant milk intake and growth up to 9 weeks of age. The incidence of full breastfeeding and breastfeeding continuation was similar with contraceptive hormonal use and no use. CLINICAL TRIALS REGISTRATION NUMBER: NCT01388582.
Assuntos
Aleitamento Materno , Desenvolvimento Infantil/efeitos dos fármacos , Anticoncepcionais Orais Combinados/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Leite Humano , Adolescente , Adulto , Desogestrel/administração & dosagem , Desogestrel/farmacologia , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente/efeitos dos fármacos , Dispositivos Intrauterinos de Cobre , Levanogestrel/administração & dosagem , Levanogestrel/farmacologia , Masculino , Leite Humano/efeitos dos fármacos , Progestinas/administração & dosagem , Progestinas/farmacologia , Adulto JovemRESUMO
Melanoma is a type of cancer that reaches more people in the world, characterized by genetic mutations that trigger the growth of disorganized cells. The diagnosis of skin tumors by invasive techniques has become a risk to the patients, so the search for new non-invasive techniques has been the subject of research in recent years. The objective of this work is to propose a non-invasive method prognosis based on the identification of specific biomarkers of the cancer, known as metabolomics analysis. For this study, we used B16F10 melanoma tumor cells and metabolic profiles were obtained at three time-periods by (1)HNMR and comparison with the cell cycle, apoptosis pathways and proliferation index. The metabolic profiles show the relationship between the metabolites found with energy metabolism, pathways of apoptosis and proliferation, which showed increases in proportion during growth and progression. Were found 29 metabolites, of which the differentially expressed are: lactate, aspartate, glycerol, lipids, alanine, myo-inositol, phosphocholine, choline, acetate, creatine and taurine. Choline and creatine are closely related with tumor progression, and are inversely expressed in later stages of tumor growth, which demonstrates the ability to be markers of tumor progression or monitoring the pharmacological efficacy when combined with other therapies. We conclude that the metabolome appeared as effective non-invasive technique predicts, besides providing possible biomarkers of melanoma.
Assuntos
Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Animais , Apoptose/genética , Caspase 3/genética , Caspase 3/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Colina/genética , Colina/metabolismo , Creatina/genética , Creatina/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Progressão da Doença , Metabolismo Energético , Feminino , Metaboloma , Metabolômica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Necrose/genética , Necrose/metabolismo , Prognóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismoRESUMO
Eleven known triterpenes (alpha-amyrin, beta-amyrin, lupeol, and their respective acetates, 3-O-acetyl derivatives of betulinic, oleanolic, and ursolic acids, cycloartenol, and tirucall-7,24-dienol), two new flavonols presenting an uncommon interglycosidic O-(1-->3) linkage (kaempferol 3-O-alpha-L-arabinofuranosyl(1-->3)-alpha-L-rhamnoside and quercetin 3-O-alpha-L-arabinofuranosyl-(1-->3)-alpha-L-rhamnoside), beta-sitosterol, stigmasterol, quercetin, and gallic acid were isolated from the Amazonian medicinal mistletoe, Cladocolea micrantha Kuijt (Loranthaceae). Their structures were established by spectral methods and eventual chromatographic comparisons. The quercetin derivative was not cytotoxic to MV3 human melanoma cells, but was able, when administered at 1 microg/mL, to promote a twofold inhibition of the migration of the cells through the transwell system when compared with paclitaxel at 5 microM.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Dissacarídeos/farmacologia , Flavonoides/química , Loranthaceae/química , Melanoma/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dissacarídeos/química , Dissacarídeos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Caules de Planta/química , Quercetina/química , Quercetina/isolamento & purificação , Solventes , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
Pectin-high amylose starch mixtures (1:4; 1:1; 4:1) were cross-linked at different degrees and characterized by rheological, thermal, X-ray diffraction and NMR analyses. For comparison, samples without cross-linker addition were also prepared and characterized. Although all samples behaved as gels, the results evidenced that the phosphorylation reaction promotes the network strengthening, resulting in covalent gels (highest critical stress, G' and recovery %). Likewise, cross-linked samples presented the highest thermal stability. However, alkaline treatment without cross-linker allowed a structural reorganization of samples, as they also behaved as covalent gels, but weaker than those gels from cross-linked samples, and presented higher thermal stability than the physical mixtures. X-ray diffractograms also evidenced the occurrence of physical and chemical modifications due to the cross-linking process and indicated that samples without cross-linker underwent some structural reorganization, resulting in a decrease of crystallinity. The chemical shift of resonance signals corroborates the occurrence of structural modifications by both alkaline treatment and cross-linking reaction.
Assuntos
Amilose/química , Reagentes de Ligações Cruzadas/química , Portadores de Fármacos , Pectinas/química , Polifosfatos/química , Química Farmacêutica , Cristalização , Preparações de Ação Retardada , Composição de Medicamentos , Géis , Temperatura Alta , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fosforilação , Reologia , Tecnologia Farmacêutica/métodos , Termogravimetria , Difração de Raios XRESUMO
Nuclear magnetic resonance studies, molecular modeling and antibacterial assays of the palladium(II) complex with S-allyl-L-cysteine (deoxyalliin) are presented. Studies based on solid and solution 13C and 15N nuclear magnetic resonance (NMR) spectroscopy confirmed that the palladium(II) complex preserved the same structural arrangement in both states, with no modifications on coordination sphere when dissolved in water. Density functional theory (DFT) studies stated that the trans isomer is the most stable one. Antibacterial activities of S-allyl-L-cysteine and its palladium(II) complex were evaluated by antibiogram assays using the disc diffusion method. The palladium(II) complex showed an effective antibacterial activity against Staphylococcus aureus (Gram-positive), Escherichia coli and Pseudomonas aeruginosa (Gram-negative) bacterial cells.
Assuntos
Antibacterianos/farmacologia , Cisteína/análogos & derivados , Testes de Sensibilidade Microbiana/métodos , Modelos Moleculares , Paládio/química , Paládio/farmacologia , Bactérias/efeitos dos fármacos , Cisteína/química , Cisteína/farmacologia , Espectroscopia de Ressonância Magnética , SoluçõesRESUMO
Potentially bioactive N-(aminoalkyl)lactamic amino acids and esters were synthesized in satisfactory to good yields by S(N)Ar reactions of aromatic acids with N-(3-aminopropyl)lactams followed by esterification with tertiary amino alcohols. The addition-elimination S(N)Ar mechanism was confirmed by NMR and MS measurements.
Assuntos
Ácido 4-Aminobenzoico/síntese química , Aminoácidos/síntese química , Ésteres/síntese química , Ácido 4-Aminobenzoico/química , Aminoácidos/química , Esterificação , Ésteres/química , Estrutura MolecularRESUMO
A rationalization of the known difference between the 3,4JC4H1 and 3,4JC1H4 couplings transmitted mainly through the 7-bridge in norbornanone is presented in terms of the effects of hyperconjugative interactions involving the carbonyl group. Theoretical and experimental studies of 3,4JCH couplings were carried out in 3-endo- and 3-exo-X-2-norbornanone derivatives (X = Cl, Br) and in exo- and endo-2-noborneol compounds. Hyperconjugative interactions were studied with the natural bond orbital (NBO) method. Hyperconjugative interactions involving the carbonyl pi*(C2=O) and sigma*(C2=O) antibonding orbitals produce a decrease of three-bond contribution to both 3,4JC4H1 and 3,4JC1H4 couplings. However, the latter antibonding orbital also undergoes a strong sigmaC3--C4 --> sigma*(C2=O) interaction, which defines an additional coupling pathway for 3,4JC4H1 but not for 3,4JC1H4. This pathway is similar to that known for homoallylic couplings, the only difference being the nature of the intermediate antibonding orbital; i.e. for 3,4JC4H1 it is of sigma*-type, while in homoallylic couplings it is of pi*-type.
RESUMO
The novel coumarinolignoid 5-methoxypropacin was isolated from the ethereal extract of the wood of the Amazonian species Protium unifoliolatum. Its structure was elucidated by spectroscopic methods as IR, 1D and 2D (1)H, (13)C-NMR and mass spectrometry. The regioisomer and the position of coumarin and arylpropanoid coupling were determined by long-distance C-H correlation (HMBC) and NOE experiments. Scopoletin and beta-sitosterol were also isolated and identified by the same physical methods.
Assuntos
Burseraceae/química , Cumarínicos/isolamento & purificação , Cumarínicos/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Fractionation of the crude methanol extract of the ascidian Cystodytes dellechiajei collected in Brazil yielded two novel alkaloids, sebastianine A (1) and sebastianine B (2). The structures of both 1 and 2 were established by analysis of spectroscopic data, indicating an unprecedented ring system for both compounds, comprising a pyridoacridine system fused with a pyrrole unit in sebastianine A (1) and a pyridoacridine system fused with a pyrrolidine system condensed with alpha-hydroxyisovaleric acid in sebastianine B (2). Both alkaloids displayed a cytotoxic profile against a panel of HCT-116 colon carcinoma cells indicative of a p53 dependent mechanism.
Assuntos
Acridinas/isolamento & purificação , Alcaloides/isolamento & purificação , Antineoplásicos/isolamento & purificação , Compostos Heterocíclicos de 4 ou mais Anéis/isolamento & purificação , Piridinas/isolamento & purificação , Urocordados/química , Acridinas/química , Acridinas/farmacologia , Alcaloides/química , Alcaloides/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Brasil , Catálise , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Concentração Inibidora 50 , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Piridinas/química , Piridinas/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismoRESUMO
Two new bromotyrosine-derived alkaloids, caissarine A (1) and caissarine B (2), along with three known biogenetically related alkaloids, aeroplysinin-1, fistularin-3, and the artifact of isolation 2-(3,5-dibromo-4-dimethoxy-1-hydroxy-2,5-cyclohexadien-1-yl)ethanamide, have been isolated from Aplysina caissara, an endemic species of marine sponge from the Southeastern Brazilian coast. The alkaloids have been identified by analysis of spectroscopic data. While caissarine A has a 2-hydroxyagmatine moiety in its structure, caissarin B is the first naturally occurring compound encompassing the unprecedented 1,7-diamino-3-hydroxyheptane moiety.