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1.
J Med Chem ; 67(17): 15438-15455, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39151117

RESUMO

Psoriasis, which severely affects the sufferer's life quality, is a chronic skin disease still lacking satisfactory medication. Recently, signal transducer and activator of transcription 3 (STAT3) was revealed playing an important role in the progression of psoriasis. In this paper, a total of 59 quinone derivatives with various scaffolds were designed, synthesized, and evaluated for antipsoriatic potential as STAT3 inhibitors. Among them, 15e was identified as the most potent antipsoriatic agent and could bind to STAT3; reduce both total and phosphorylated STAT3 levels, inhibit the nuclear translocation of STAT3; and, therefore, inhibit the transcription and expression of the propsoriatic factor IL-17A. In vivo experiments on mice showed that the topical application of 15e was effective in alleviating IMQ-induced psoriasis without noticeable side effects. In all, this research rendered 15e as a promising drug candidate for psoriasis.


Assuntos
Desenho de Fármacos , Psoríase , Fator de Transcrição STAT3 , Psoríase/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Animais , Humanos , Camundongos , Interleucina-17/metabolismo , Interleucina-17/antagonistas & inibidores , Quinonas/farmacologia , Quinonas/síntese química , Quinonas/uso terapêutico , Quinonas/química , Relação Estrutura-Atividade , Camundongos Endogâmicos BALB C
2.
Bioorg Chem ; 151: 107617, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39053100

RESUMO

Psoriasis is a troublesome scaling skin disease with no high-effective medication available by far. Signal transducer and activator of transcription 3 (STAT3) has recently been revealed as a crucial player in the pathogenesis and progression of psoriasis and emerged as an intriguing antipsoriatic drug target. Naturally occurring lapachol and its quinone analogs had been discovered as effective STAT3 inhibitors, however, their antipsoriatic effects are not well investigated. Previously, we have reported a series of isothiazoloquinone lapachol derivatives. Here, the antipsoriastic potentials of these isothiazoloquinones were investigated and, in addition, 35 novel isoxazoloquinone derivatives were prepared and studied for their anti-psoriasis properties. Among them, the most potent antipsoriatic compound B20 determined by in vitro test on HaCaT cells could directly bind to STAT3, reduce STAT3 level and inhibit STAT3 nuclear translocation. In vivo studies showed that topical application of B20 could effectively alleviate IMQ-induced psoriasis in mice with no obvious side effects. In addition, B20 inhibited the production of interleukin 17 (IL-17A), a STAT3-downstream cytokine essential for the progression of psoriasis, both in vitro and in vivo. Thus, isoxazoloquinone B20 is a potent STAT3-targeting antipsoriatic agent worth of further investigation.


Assuntos
Psoríase , Fator de Transcrição STAT3 , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Psoríase/tratamento farmacológico , Humanos , Animais , Camundongos , Relação Estrutura-Atividade , Estrutura Molecular , Naftoquinonas/farmacologia , Naftoquinonas/química , Naftoquinonas/síntese química , Isoxazóis/farmacologia , Isoxazóis/química , Isoxazóis/síntese química , Relação Dose-Resposta a Droga , Camundongos Endogâmicos BALB C
3.
Adv Sci (Weinh) ; : e2400049, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38952055

RESUMO

In recent years, cancer immunotherapy has undergone a transformative shift toward personalized and targeted therapeutic strategies. Bacteria-derived outer membrane vesicles (OMVs) have emerged as a promising and adaptable platform for cancer immunotherapy due to their unique properties, including natural immunogenicity and the ability to be engineered for specific therapeutic purposes. In this review, a comprehensive overview is provided of state-of-the-art techniques and methodologies employed in the engineering of versatile OMVs for cancer immunotherapy. Beginning by exploring the biogenesis and composition of OMVs, unveiling their intrinsic immunogenic properties for therapeutic appeal. Subsequently, innovative approaches employed to engineer OMVs are delved into, ranging from the genetic engineering of parent bacteria to the incorporation of functional molecules. The importance of rational design strategies is highlighted to enhance the immunogenicity and specificity of OMVs, allowing tailoring for diverse cancer types. Furthermore, insights into clinical studies and potential challenges utilizing OMVs as cancer vaccines or adjuvants are also provided, offering a comprehensive assessment of the current landscape and future prospects. Overall, this review provides valuable insights for researchers involved in the rapidly evolving field of cancer immunotherapy, offering a roadmap for harnessing the full potential of OMVs as a versatile and adaptable platform for cancer treatment.

4.
J Nat Prod ; 86(9): 2111-2121, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37682035

RESUMO

Spinosyn A (SPA), derived from a soil microorganism, Saccharopolyspora spinosa, and its derivative, LM2I, has potential inhibitory effects on a variety of cancer cells. However, the effects of SPA and LM2I in inhibiting the growth of human colorectal cancer cells and the molecular mechanisms underlying these effects are not fully understood. Cell viability was tested by using a 3-(4,5-dimethylthiazol-2-yl-)-2,5-diphenyltetrazolium bromide (MTT) assay and a colony formation assay. On the basis of the IC50 values of SPA and LM2I in seven colorectal cancer (CRC) cell lines, sensitive (HT29 and SW480) and insensitive (SW620 and RKO) cell lines were screened. The GSE2509 and GSE10843 data sets were used to identify 69 differentially expressed genes (DEGs) between sensitive and insensitive cell lines. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and protein-protein interactions (PPI) were performed to elucidate the molecular mechanisms of the DEGs. The hub gene of the DEGs was detected by Western blot analysis and verified using the CRISPR/Cas9 system. Our data indicate that SPA and its derivative LM2I have significant antiproliferative activity in seven colorectal cancer cell lines and colorectal xenograft tumors. On the basis of bioinformatics analysis, it was demonstrated that epidermal growth factor receptor (EGFR) was the hub gene of the DEGs and was associated with the inhibitory effects of SPA and LM2I in CRC cell lines. The study also revealed that SPA and LM2I inhibited the EGFR pathway in vitro and in vivo.


Assuntos
Neoplasias Colorretais , Macrolídeos , Humanos , Receptores ErbB , Bioensaio , Neoplasias Colorretais/tratamento farmacológico
5.
Cancers (Basel) ; 15(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37173892

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, with shorter five-year survival than other breast cancer subtypes, and lacks targeted and hormonal treatment strategies. The signal transducer and activator of transcription 3 (STAT3) signaling is up-regulated in various tumors, including TNBC, and plays a vital role in regulating the expression of multiple proliferation- and apoptosis-related genes. RESULTS: By combining the unique structures of the natural compounds STA-21 and Aulosirazole with antitumor activities, we synthesized a class of novel isoxazoloquinone derivatives and showed that one of these compounds, ZSW, binds to the SH2 domain of STAT3, leading to decreased STAT3 expression and activation in TNBC cells. Furthermore, ZSW promotes STAT3 ubiquitination, inhibits the proliferation of TNBC cells in vitro, and attenuates tumor growth with manageable toxicities in vivo. ZSW also decreases the mammosphere formation of breast cancer stem cells (BCSCs) by inhibiting STAT3. CONCLUSIONS: We conclude that the novel isoxazoloquinone ZSW may be developed as a cancer therapeutic because it targets STAT3, thereby inhibiting the stemness of cancer cells.

6.
Transl Cancer Res ; 12(1): 46-64, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36760376

RESUMO

Background: Hepatocellular carcinoma (HCC) is a common malignancy. Ferroptosis and cuproptosis promote HCC spread and proliferation. While fewer studies have combined ferroptosis and cuproptosis to construct prognostic signature of HCC. This work attempts to establish a novel scoring system for predicting HCC prognosis, immunotherapy, and medication sensitivity based on ferroptosis-related genes (FRGs) and cuproptosis-related genes (CRGs). Methods: FerrDb and previous literature were used to identify FRGs. CRGs came from original research. The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases included the HCC transcriptional profile and clinical information [survival time, survival status, age, gender, Tumor Node Metastasis (TNM) stage, etc.]. Correlation, Cox, and least absolute shrinkage and selection operator (LASSO) regression analyses were used to narrow down prognostic genes and develop an HCC risk model. Using "caret", R separated TCGA-HCC samples into a training risk set and an internal test risk set. As external validation, we used ICGC samples. We employed Kaplan-Meier analysis and receiver operating characteristic (ROC) curve to evaluate the model's clinical efficacy. CIBERSORT and TIMER measured immunocytic infiltration in high- and low-risk populations. Results: TXNRD1 [hazard ratio (HR) =1.477, P<0.001], FTL (HR =1.373, P=0.001), GPX4 (HR =1.650, P=0.004), PRDX1 (HR =1.576, P=0.002), VDAC2 (HR =1.728, P=0.008), OTUB1 (HR =1.826, P=0.002), NRAS (HR =1.596, P=0.005), SLC38A1 (HR =1.290, P=0.002), and SLC1A5 (HR =1.306, P<0.001) were distinguished to build predictive model. In both the model cohort (P<0.001) and the validation cohort (P<0.05), low-risk patients had superior overall survival (OS). The areas under the curve (AUCs) of the ROC curves in the training cohort (1-, 3-, and 5-year AUCs: 0.751, 0.727, and 0.743), internal validation cohort (1-, 3-, and 5-year AUCs: 0.826, 0.624, and 0.589), and ICGC cohort (1-, 3-, and 5-year AUCs: 0.699, 0.702, and 0.568) were calculated. Infiltration of immune cells and immunological checkpoints were also connected with our signature. Treatments with BI.2536, Epothilone.B, Gemcitabine, Mitomycin.C, Obatoclax. Mesylate, and Sunitinib may profit high-risk patients. Conclusions: We analyzed FRGs and CRGs profiles in HCC and established a unique risk model for treatment and prognosis. Our data highlight FRGs and CRGs in clinical practice and suggest ferroptosis and cuproptosis may be therapeutic targets for HCC patients. To validate the model's clinical efficacy, more HCC cases and prospective clinical assessments are needed.

7.
Transl Cancer Res ; 12(12): 3327-3345, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38192999

RESUMO

Background: Ferroptosis and cuproptosis play a crucial role in the progression and dissemination of hepatocellular carcinoma (HCC). The primary objective of this study was to develop a unique scoring system for predicting the prognosis and immunological landscape of HCC based on ferroptosis-related genes (FRGs) and cuproptosis-related genes (CRGs). Methods: As the training cohort, we assembled a novel HCC cohort by merging gene expression data and clinical data from The Cancer Genome Atlas (TCGA) database, and Gene Expression Omnibus (GEO) database. The validation cohort consisted of 230 HCC cases taken from the International Cancer Genome Consortium (ICGC) database. Multiple genomic characteristics, such as tumor mutation burden (TMB), and copy number variations were analyzed concurrently. On the basis of the expression of CRGs and FRGs, patients were classified into cuproptosis and ferroptosis subtypes. Then, we constructed a risk model using least absolute shrinkage and selection operator (LASSO) analysis and Cox regression analysis based on ferroptosis and cuproptosis-related differentially expressed genes (DEGs). Patients were separated into two groups according to median risk score. We compared the immunophenotype, tumor microenvironment (TME), cancer stem cell index, and treatment sensitivity of two groups. Results: Three subtypes of ferroptosis and two subtypes of cuproptosis were identified among the patients. A greater likelihood of survival (P<0.05) was expected for patients in FRGcluster B and CRGcluster B. After that, a confirmed risk signature for ferroptosis and cuproptosis was developed and tested. Patients in the low-risk group had significantly higher survival rates than those in the high-risk group, according to our study (P<0.001). There was also a strong correlation between the signature and other variables including immunophenoscore, TMB, cancer stem cell index, immunological checkpoint genes, and sensitivity to chemotherapeutics. Conclusions: Through this comprehensive research, we identified a unique risk signature associated with HCC patients' treatment status and prognosis. Our findings highlight FRGs' and CRGs' significance in clinical practice and imply ferroptosis and cuproptosis may be therapeutic targets for HCC patients.

8.
Nat Commun ; 12(1): 2263, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859183

RESUMO

Argininosuccinate synthase (ASS1) is a ubiquitous enzyme in mammals that catalyzes the formation of argininosuccinate from citrulline and aspartate. ASS1 genetic deficiency in patients leads to an autosomal recessive urea cycle disorder citrullinemia, while its somatic silence or down-regulation is very common in various human cancers. Here, we show that ASS1 functions as a tumor suppressor in breast cancer, and the pesticide spinosyn A (SPA) and its derivative LM-2I suppress breast tumor cell proliferation and growth by binding to and activating ASS1. The C13-C14 double bond in SPA and LM-2I while the Cys97 (C97) site in ASS1 are critical for the interaction between ASS1 and SPA or LM-2I. SPA and LM-2I treatment results in significant enhancement of ASS1 enzymatic activity in breast cancer cells, particularly in those cancer cells with low ASS1 expression, leading to reduced pyrimidine synthesis and consequently the inhibition of cancer cell proliferation. Thus, our results establish spinosyn A and its derivative LM-2I as potent ASS1 enzymatic activator and tumor inhibitor, which provides a therapeutic avenue for tumors with low ASS1 expression and for those non-tumor diseases caused by down-regulation of ASS1.


Assuntos
Argininossuccinato Sintase/metabolismo , Neoplasias da Mama/tratamento farmacológico , Citrulinemia/tratamento farmacológico , Ativadores de Enzimas/farmacologia , Macrolídeos/farmacologia , Proteínas Supressoras de Tumor/agonistas , Adulto , Idoso , Animais , Argininossuccinato Sintase/genética , Argininossuccinato Sintase/isolamento & purificação , Ácido Aspártico/metabolismo , Mama/patologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citrulina/metabolismo , Citrulinemia/genética , Ativadores de Enzimas/uso terapêutico , Feminino , Técnicas de Silenciamento de Genes , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Macrolídeos/uso terapêutico , Metabolômica , Camundongos , Pessoa de Meia-Idade , Simulação de Acoplamento Molecular , Mutação , Ligação Proteica , Pirimidinas/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Bioorg Med Chem Lett ; 30(16): 127286, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32631508

RESUMO

Natural quinones and their analogues have attracted growing attention because of their novel anticancer activities. A series of novel isothiazoloquinoline quinone analogues were synthesized and evaluated for antitumor activities against four different kind of cancer cells. Among them, isothiazoloquinolinoquinones inhibited cancer cells proliferation effectively with IC50 values in the nanomolar range, and isothiazoloquinolinoquinone 13a induced the cell apoptosis. Further exploration of possible mechanism of action indicates that 13a not only activates ROS production through NQO1-directed redox cycling but also inhibits the phosphorylation of STAT3. These findings indicate that 13a has potential use for the development of new skeleton drug candidate as an efficient substrate of NQO1 and STAT3 inhibitor.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , Quinonas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Oxirredução , Quinonas/síntese química , Quinonas/química , Fator de Transcrição STAT3/metabolismo , Relação Estrutura-Atividade
10.
Bioorg Med Chem Lett ; 30(9): 127047, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32139325

RESUMO

A series of DLC (delocalized lipophilic cation) modified spinosyn derivatives were synthesized and evaluated for antitumor efficacies both in vitro and in vivo. Cancer cell based antiproliferative assays indicated that the more lipophilic derivatives had stronger inhibitory effects on the tested cancer cell lines. Compound 7b and 8b exhibited strong anti-OXPHOS and apoptosis inducing ability. Notable antitumor efficacies of 7b (5 mg/kg) and 8b (2.5 mg/kg) were observed in the in vivo tumor xenograft experiments, however, lethal toxicities were observed on higher dosages. Our findings indicated that DLC modification is a viable strategy to enhance the anti-OXPHOS and antitumor efficacies of spinosyn derivatives.


Assuntos
Macrolídeos/síntese química , Macrolídeos/farmacologia , Mitocôndrias/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Animais , Antineoplásicos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Relação Estrutura-Atividade
11.
Org Lett ; 21(15): 6117-6121, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31322353

RESUMO

A convenient Fe-catalyzed four-component radical dual difunctionalization and ordered assembly of two alkenes with aromatic/aliphatic aldehydes and TBHP to provide chain elongated ß,δ-functionalized ketones via a one-pot procedure has been developed. Aldehydes were homolytically cleavaged to produce acyl radicals and subsequently allowed for the successive construction of C(sp2)-C(sp3), C(sp3)-C(sp3), and C(sp3)-O bonds via dual radical insertions and radical-radical coupling, following the intrinsic nucleo/electrophilic reactivity of both the radicals and alkenes.

12.
Bioorg Med Chem Lett ; 28(20): 3346-3349, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30201293

RESUMO

In order to enhance the mitochondria-targeting ability of spinosad. A series of quartenary ammonium spinosyn derivatives was designed and synthesized. Some of the derivatives displayed greatly enhanced antiproliferative ability towards tested human cancer cell lines. The structure activity relationship study indicated that lipophilicity has a great influence on the antiproliferative effects of these derivatives. The most active compound 11d exhibited remarkably enhanced OXPHS inhibition and apoptosis inducing ability than spinosyn A.


Assuntos
Antineoplásicos/farmacologia , Macrolídeos/farmacologia , Compostos de Amônio Quaternário/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Macrolídeos/síntese química , Macrolídeos/química , Mitocôndrias/metabolismo , Estrutura Molecular , Fosforilação Oxidativa/efeitos dos fármacos , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/química , Relação Estrutura-Atividade
13.
Anticancer Agents Med Chem ; 18(8): 1156-1162, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29607789

RESUMO

BACKGROUND: The heptaprotective flavonolignan silibinin and dehydrosilibinin have exhibited moderate antiproliferative activities toward many cancer cell lines. Considering of the nontoxic profile of these natural products, chemical modification to enhance the anticancer potentials is promising. METHOD: A series of 7-O-aminoalkyl-2,3-dehydrosilibinin derivatives were synthesized and evaluated for their antiproliferative activities against several cancer cell lines. RESULTS: A number of the synthesized dehydrosilibinin derivatives exhibited greatly enhanced potency with 50% growth inhibition at low micromolar concentrations. Structure activity study indicated that the distance between N and 7-O on the side chain has a limited influence on the antiproliferative activity, while the presence of a morpholino group decreases the antiproliferative activities dramatically. Flow cytometry based assays on human colon cancer HCT116 cells revealed that 6a and 6c, two of the most potent derivatives, effectively arrested the cell cycle in the G2 phase and stimulated cell apoptosis. CONCLUSION: Our findings suggest that attaching an appropriate tertiary amino alkyl side chain through 7-Oalkylation on 2,3-dehydrosilibinin, would be a viable strategy for the development of silibinin derivatives as anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Silibina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Silibina/síntese química , Silibina/química , Relação Estrutura-Atividade
14.
Org Biomol Chem ; 15(34): 7112-7116, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28825437

RESUMO

An iodine-catalyzed multiple C-H bond functionalization of isoquinolines with methylarenes via a successive benzylic sp3 C-H iodination/N-benzylation/amidation/double sp2 C-H oxidation sequence is developed. This reaction utilizes un-functionalized isoquinolines and readily available methylarenes as starting materials, proceeds under metal-free conditions, and avoids a multi-step experimental operation, to make it an efficient and practical method for the synthesis of N-benzyl isoquinoline-1,3,4-triones.

15.
Zhongguo Zhong Yao Za Zhi ; 33(5): 517-21, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18536372

RESUMO

OBJECTIVE: To study the chemical constituents in roots of Caragana sinica. METHOD: The constituents were isolated by silica gel column chromatography, and their structures were identified by spectroscopic methods. RESULT: Seven compounds were identified as (+) - stenophyllol B (1), 4-hydroxybenzoic acid (2), odoratin (3), resveratrol (4), cararosinol A (5), leachinol C (6), carasinaurone (7) respectively. CONCLUSION: Compound 1 was a new compound which was the enantiomer of stenophyllol B. Compounds 2-6 were obtained from the plant for the first time.


Assuntos
Caragana/química , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química , Cromatografia em Gel , Medicamentos de Ervas Chinesas/análise , Estrutura Molecular , Parabenos/análise , Parabenos/química , Resveratrol , Estilbenos/análise , Estilbenos/química
16.
J Org Chem ; 73(11): 4087-91, 2008 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-18459810

RESUMO

Biotransformations of a number of racemic beta-hydroxy and beta-amino nitrile derivatives were studied using Rhodococcus erythropolis AJ270, the nitrile hydratase and amidase-containing microbial whole cell catalyst, under very mild conditions. The overall enantioselectivity of nitrile biotransformations was governed predominantly by the amidase whose enantioselectivity was switched on remarkably by an O- and a N-benzyl protection group of the substrates. While biotransformations of beta-hydroxy and beta-amino alkanenitriles gave low yields of amide and acid products of very low enantiomeric purity, introduction of a simple benzyl protection group on the beta-hydroxy and beta-amino of nitrile substrates led to the formation of highly enantioenriched beta-benzyloxy and beta-benzylamino amides and acids in almost quantitative yield. The easy protection and deprotection operations, high chemical yield, and excellent enantioselectivity render the nitrile biotransformation a useful protocol in the synthesis of enantiopure beta-hydroxy and beta-amino acids.


Assuntos
Amidas/química , Amidoidrolases/química , Aminoácidos/química , Nitrilas/química , Biotransformação , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Rhodococcus/enzimologia , Estereoisomerismo
17.
Org Lett ; 8(15): 3231-4, 2006 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-16836373

RESUMO

[Structure: see text] Catalyzed by the Rhodococcus erythropolis AJ270 whole cell catalyst, the O-benzylated beta-hydroxy alkanenitriles underwent remarkably high enantioselective biotransformations, whereas the biotransformations of free beta-hydroxy alkanenitriles gave very low enantioselectivity. The easy manipulations of O-protection and O-deprotection, excellent chemical and enantiomeric yields of biotransformations, along with the scalability render this enzymatic transformation attractive and practical for the synthesis of highly enantiopure beta-hydroxy alkanoic acids and their amide derivatives.


Assuntos
Derivados de Benzeno/química , Ácidos Carboxílicos/síntese química , Nitrilas/química , Rhodococcus/metabolismo , Amidas/química , Biotransformação , Catálise , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
18.
J Asian Nat Prod Res ; 6(4): 241-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15621582

RESUMO

A new resveratrol dimer, carasiphenol A (1), and a new resveratrol trimer, carasiphenol B (2), have been isolated from the aerial parts of Caragana sinica. Their structures have been elucidated from spectroscopic evidence, especially HMBC and NOE experiments. The relative configuration of the known dimer pallidol (6) was confirmed by X-ray diffraction.


Assuntos
Caragana/química , Medicamentos de Ervas Chinesas/química , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/isolamento & purificação , Conformação Molecular , Estrutura Molecular , Componentes Aéreos da Planta/química
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