Antitumor promoting activities of 3-O-acyl-(−)-epigallocatechins

Uesato, Shinichi; Kitagawa, Yoshikazu; Hara, Yukihiko; Tokuda, Harukuni; Okuda, Masumi; Mou, Xiao; Mukainaka, Teruo; Nishino, Hoyoku

doi:10.1016/s0960-894x(00)00314-0

Cited by 26 publications

(29 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As shown in Table 1, the (ϩ)-catechin derivatives 11, 5, and 6 with an acyl chain of carbon atoms C 8 -C 11 had more effect (percentage EBV-EA activationsϭ7.2, 8.8, and 10.7%, respectively) than the original (ϩ)-catechin (1) (21.6%) at 1ϫ10 3 mol ratios/TPA although they were slightly less effective than the corresponding (Ϫ)-EGC derivatives (percentage activationsϭ5.0-9.3%). 1) Furthermore, either shortening C 8 (in 5) or lengthening C 10 (in 6) led to a reduction in the inhibitory activity as in the case of 3-O-acyl-(Ϫ)-EGCs. Therefore the (ϩ)-catechin derivatives possessing an acyl chain of carbon atoms C 8 to C 11 could be substitutes for the corresponding 3-O-acyl-(Ϫ)-EGCs.…”

Section: Results and Disscussionmentioning

confidence: 98%

“…The EGCs with the C-3 acyl chain of C 8 -C 11 carbon atoms showed marked antitumor-promoting activities both in the Epstein-Barr virus early antigen (EBV-EA) activation test and in the two-stage mouse skin carcinogenesis test were found to be especially promising candidates for cancer chemoprevention. 1,2) In the present work, we examined the inhibitory effects of 3-O-acyl derivatives of (ϩ)-catehin (1) against the activation of the EBV-EA since 1 is available at much lower price from Gambir (Asenyaku in Japanese, natural medicine, Uncaria gambir ROXB. listed in the Japanese Pharmacopoeia XIV) 5) than green tea catechins and thus could be a substitute for (Ϫ)-EGC (2) as a synthetic starting material of catechins with a 3-O-acyl group.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Inhibitory Effects of 3-O-Acyl-(+)-catechins on Epstein-Barr Virus Activation

Uesato

Taniuchi

Kumagai

et al. 2003

CHEMICAL & PHARMACEUTICAL BULLETIN

Self Cite

View full text Add to dashboard Cite

As an exploratory investigation of antitumor-promoting catechins, we tried to synthesize the (Ϫ)-epigallocatechins (EGCs) possessing an acyl group.1,2) An acyl group was introduced at the C-3 hydroxy group of (Ϫ)-EGC (2), which is less responsible for radical-scavenging action than the phenolic hydroxyl groups, 3,4) to improve their pharmacokinetic profile such as cell membrane and tissue permeability. The EGCs with the C-3 acyl chain of C 8 -C 11 carbon atoms showed marked antitumor-promoting activities both in the Epstein-Barr virus early antigen (EBV-EA) activation test and in the two-stage mouse skin carcinogenesis test were found to be especially promising candidates for cancer chemoprevention. 1,2) In the present work, we examined the inhibitory effects of 3-O-acyl derivatives of (ϩ)-catehin (1) against the activation of the EBV-EA since 1 is available at much lower price from Gambir (Asenyaku in Japanese, natural medicine, Uncaria gambir ROXB. listed in the Japanese Pharmacopoeia XIV) 5) than green tea catechins and thus could be a substitute for (Ϫ)-EGC (2) as a synthetic starting material of catechins with a 3-O-acyl group. Chemistry(ϩ)-Catechin (1) was reacted with straight-chain acid chlorides of C 4 to C 18 in tetrahydrofuran in the presence of trifluoroacetic acid.1) Preparative HPLC (GS-320 column) of the reaction mixtures gave 3-O-acyl-(ϩ)-catechins: 3, 6) 4, 5, 6, 6) 7, 8, 9, 7) and 10 in 7.7% to 16.8% yields. Furthermore, the (ϩ)-catechin derivative 11 possessing the (RS)-2-methyloctanoyl chain was synthesized by the same method as above in the expectation that it would avoid the enzyme-catalyzed hydrolytic cleavage of the ester bond in the body as in the case of the corresponding (Ϫ)-EGC derivatives. 2) Results and DisscussionThe antitumor-promoting efficacy of the synthetic 3-Oacyl-(ϩ)-catechins was estimated by measuring the inhibitory effects against the activation of EBV-EA in Raji cells induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). The assays were performed in triplicate for each compound. No sample exhibited significant toxicity against Raji cells. As shown in Table 1, the (ϩ)-catechin derivatives 11, 5, and 6 with an acyl chain of carbon atoms C 8 -C 11 had more effect (percentage EBV-EA activationsϭ7.2, 8.8, and 10.7%, respectively) than the original (ϩ)-catechin (1) In the course of an exploratory investigation of antitumor-promoting catechins, 3-O-acyl-(؉)-catechins of varying carbon lengths from C 4 to C 18 were assessed for inhibitory effects on the activation of the Epstein-Barr virus early antigen. Like 3-O-acyl-(؊)-epigallocatechins, the (؉)-catechin derivatives showed promising effects with the C-3 acyl chain of C 8 -C 11 carbon atoms.

show abstract

Section: Results and Disscussionmentioning

confidence: 98%

mentioning

confidence: 99%

Inhibitory Effects of 3-O-Acyl-(+)-catechins on Epstein-Barr Virus Activation

Uesato

Taniuchi

Kumagai

et al. 2003

CHEMICAL & PHARMACEUTICAL BULLETIN

Self Cite

View full text Add to dashboard Cite

show abstract

“…Catechins and its derivatives showed various pharmacological activities viz antimutagenic (Paschka et al 1998), antioxidant (Gadow et al 1997, antibacterial (Hu et al 2001;Stapleton et al 2004;Park and Cho 2010), anticancer activities (Uesato et al 2000;Kumar et al 2015), and prevention of atherosclerosis (Miura et al 2001;Chyu et al 2004). Catechins face one of the major limitations.…”

Section: Introductionmentioning

confidence: 99%

Antimicrobial and docking studies of (−)-catechin derivatives

Kumar

Poornima

Kushwaha

et al. 2015

J Korean Soc Appl Biol Chem

View full text Add to dashboard Cite

Antimicrobial activities of (-)-catechin derivatives were assayed for their antibacterial and antifungal activities against gram positive, gram negative bacteria, and fungi. Most of the compounds significantly active among which Compounds 1a, 1b, and 1c showed excellent antibacterial for both gram negative and gram positive bacteria, these compounds also exhibited excellent antifungal activity more than the standard drug. Molecular docking studies of Compounds 1a and 1b established good binding affinity with ATP-binding pocket of DNA gyrase and are in favor of the observed biological activity. These data collectively suggest that Compounds 1a and 1b could serve as a novel antimicrobial agent.

show abstract

“…4) It has been reported that several newly synthesized 3-O-acyl-(+)-catechins, as well as 3-O-acyl-(-)-epigallocatechins, inhibited the activation of the Epstein-Barr virus early antigen more strongly than catechins lacking the 3-O-acyl group. 5,6) 3-OOctanoyl-(+)-catechin was one of the most effective derivatives. The evidence suggests that modification of 3-OH group of catechins could enhance the biological functions of the original catechins.…”

Section: Introductionmentioning

confidence: 99%