Methyluracil and 5-nitro-6-methyluracil react with variable molar quantities of benzoyl chloride in acetonitrile-pyridine at room temperature to give 1-N, 3-N-dibenzoyl-6- methyluracil 3b and 1-N-benzoyl-5-nitro-6-met...Methyluracil and 5-nitro-6-methyluracil react with variable molar quantities of benzoyl chloride in acetonitrile-pyridine at room temperature to give 1-N, 3-N-dibenzoyl-6- methyluracil 3b and 1-N-benzoyl-5-nitro-6-methyluracil 4b. The reactive rates of debenzoylation of 3b and 4b were investigated.展开更多
1-Alkyl-5-amino-6-phenylethyluracils (1a, 1b) were synthesized as potential non-nucleoside HIV-1RT inhibitors. A convenient synthetic procedure was developed for the preparation of 1-alkyl-5-amino or 5-aminosubstitu...1-Alkyl-5-amino-6-phenylethyluracils (1a, 1b) were synthesized as potential non-nucleoside HIV-1RT inhibitors. A convenient synthetic procedure was developed for the preparation of 1-alkyl-5-amino or 5-aminosubstituted-6-phenylethyluracils, which were synthesized in three or four steps from 6-methyluracil in good yield. The development of a one-pot reaction that simultaneously removed the benzyl protection group and reduced the nitro group greatly improved the yield of the synthesis. Compounds 1a and 1b are analogs of MKC-442, which is an efficient inhibitor of HIV-1 reverse transcriptase, 1a and 1b were tested for their inhibition of HIV-1RT, and moderate activity was found for 1a.展开更多
We report the characterization of a uracil-DNA glycosylase(UDG) from the hyperthermophilic archaea Pyrococcus furiosus(P, furiosus). P. furiosus UDG(PfUDG) has high sequence similarity to the families IV and V U...We report the characterization of a uracil-DNA glycosylase(UDG) from the hyperthermophilic archaea Pyrococcus furiosus(P, furiosus). P. furiosus UDG(PfUDG) has high sequence similarity to the families IV and V UDGs(thermostable UDG family and PaUDG-b family). PfUDG excises uracil from various DNA substrates with the following order: U/T=U/C〉U/G=U/AP=U/-〉U/U=U/I=U/A. The optimal temperature and pH value for uracil exci- sion by PfUDG are 70 ℃ and 9.0, respectively. The removal of U is inhibited by the divalent ions of Fe, Ca, Zn, Cu, Co, Ni and Mn, as well as a high concentration of NaC1. The phosphorothioates near uracil strongly inhibit the exci- sion of uracil by PfUDG. Interestingly, pfuDNA(Pyrococcusfuriosus DNA) polymerase, which tightly binds the ura- cil-carrying oligonucleotide, does not inhibit the excision by Pfl.IDG, suggesting PfUDG in vivo functions as the re- pair enzyme to excise uracil damage in genome.展开更多
For the uracil-BX3 (X = F, Cl) systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals (B3LYP) method of density functional theory (DFT) and the second-o...For the uracil-BX3 (X = F, Cl) systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals (B3LYP) method of density functional theory (DFT) and the second-order Moller-Plesset (MP2) method of ab initio at the 6- 311 +G^* or 6-311 ++G^* basis set. Four isomers were found for each system, and then the single-point energy evaluations were performed using the larger basis sets of (6-311 +G(2df, p) and aug-cc-pVDZ with DFF method. In the most stable isomer of uracil-BF3 or uracil-BCl3, the boron atom of BX3 (X = F, Cl) connects to the carbonyl oxygen O7 of uracil with a stabilization energy of -46.56 or -31.10 kJ/mol at the B3LYP/6-31 1+G^* level (BSSE corrected). The analyses for combining interaction between BX3 and uracil with the atom-in-molecule theory (AIM) and natural bond orbital method (NBO) have been performed. The results indicate that all isomers were formed with σ-p type interactions between uracil and BX3, in which the carbonyl oxygen offers its lone pair electrons to the empty p orbital of boron atom and the concomitances of charge transfer from uracil to BX3 occur. Moreover, there exists one or two hydrogen bonds in most isomers of uracil-BX3 system and these hydrogen bonds contribute to the stability of the complex systems. Frequency analysis suggests that the stretching vibration of BX3 undergoes a red shift in complexes. Uracil-BF3 complex is more stable than uracil-BCl3 although the distance of B-O is shorter in the latter. Besides, the conversion mechanisms between different isomers of uracil-BF3 have been obtained.展开更多
One practical and industrial procedure for preparation of 5-hydroxymethyluracil has been developed. This method has the advantage of facile operation, low cost and stable yield.
Background: We evaluated the feasibility and efficacy of irinotecan (CPT-11) plus tegafur/uracil (UFT) combination chemotherapy in patients with advanced colorectal cancer. Patients and Methods: PK parameters were con...Background: We evaluated the feasibility and efficacy of irinotecan (CPT-11) plus tegafur/uracil (UFT) combination chemotherapy in patients with advanced colorectal cancer. Patients and Methods: PK parameters were concurrently measured to confirm the presence of drug interactions in this treatment schedule. CPT-11 was administered intravenously at the dose of 150 mg/m2 on days 1, 15. UFT was administered at the dose of 375 mg/m2/day (B.I.D.) on days 3 - 7, 10 - 14, 17 - 21, 24 - 28 repeated every 5 weeks. Results: 31 patients were enrolled. PK parameters for CPT-11, FT, 5-FU and uracil are available from 5 patients. The overall response rate was 16.1%. The median time to treatment discontinuation was 3.9 months. There was no significant difference in PK parameters of CPT-11 between day 1 and day 15 and of UFT between day 3 and day 10. Conclusion: CPT-11 plus UFT combination chemotherapy exhibited a tolerable toxicity profile with acceptable efficacy. Pharmacokinetic analysis showed that there were no drug interactions in this treatment schedule.展开更多
A new series of compounds, 1-[(O,O-diphenyl phosphonyl)arylmethylene aminocarbonylmethyl]uracils, were synthesized in yield of 54.6-72.0% with DCC/BtOH as the coupling reagent, and their biological activities are bein...A new series of compounds, 1-[(O,O-diphenyl phosphonyl)arylmethylene aminocarbonylmethyl]uracils, were synthesized in yield of 54.6-72.0% with DCC/BtOH as the coupling reagent, and their biological activities are being tested.展开更多
Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, including Japan. Although the development of imaging modalities has made the early diagnosis of HCC possible, surgically resectable case...Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, including Japan. Although the development of imaging modalities has made the early diagnosis of HCC possible, surgically resectable cases are relatively uncommon because of hepatic function reserve and/or an advanced stage at presentation. Several modalities, such as transcatheter arterial chemoembolization, percutaneous ethanol injection, microwave coagulation therapy and radiofrequency ablation are reportedly useful in treating patients with non-resectable disease. However, unfortunately, many HCC patients have tumor recurrence. The overall prognosis of patients with HCC is very poor, and treatment of the advanced form is still problematic. In this article, we review the clinical efficacy and toxicity of enteric-coated tegafur/uracil in the treatment of patients with advanced non-resectable HCC.展开更多
Tegafur-uracil has been reported to have only minor adverse effects and is associated with liver injury in 1.79% of Japanese patients. The development of tegafur-uracil-induced hepatic fibrosis with portal hypertensio...Tegafur-uracil has been reported to have only minor adverse effects and is associated with liver injury in 1.79% of Japanese patients. The development of tegafur-uracil-induced hepatic fibrosis with portal hypertension is rare. Here, we report a case of a 74-year-old woman with rapidly developing tegafururacil-induced hepatic fibrosis. The patient had no history of liver disease and had been treated with tegafur-uracil for 8 mo after breast cancer surgery. The patient was admitted to our hospital for abdominal distension and leg edema associated with liver dysfunction. Computed tomography imaging revealed massive ascites and splenomegaly, and a non-invasive assessment of liver fibrosis indicated advanced fibrosis. The histopathological findings revealed periportal fibrosis and bridging fibrosis with septation. The massive ascites resolved after discontinuing tegafururacil. These findings suggest that advanced hepatic fibrosis can develop from a relatively short-term administration of tegafur-uracil and that non-invasive assessment is useful for predicting hepatic fibrosis.展开更多
Michael addition reactions of uracil to acrylates were catalyzed by an alkaline protease from Bacillus subtilis in dimethyl sulfoxide at 55 ℃ for 72 h. The adducts were determined by TLC, IR and 1H NMR.
The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N- methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final pr...The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N- methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final product was obtained in 20.8% yield.展开更多
The photolysis of uracil in phosphate-buffered saline (PBS, pH 8.0) under the irradiation pf medium pressure mercury lamp (MPML) leads to the production of a novel compound C4H5N2O6P. The composition and structure of ...The photolysis of uracil in phosphate-buffered saline (PBS, pH 8.0) under the irradiation pf medium pressure mercury lamp (MPML) leads to the production of a novel compound C4H5N2O6P. The composition and structure of the compound has been identified by elemental analysis, EI-MS, UV, IR, H-1, C-13, P-31-NMR.展开更多
6-aminouracil 1 was utilized to introduce different heterocyclic rings at C-6 position through various synthetic strategies. The synthesized compounds bear rings that are either directly attached to the uracil back bo...6-aminouracil 1 was utilized to introduce different heterocyclic rings at C-6 position through various synthetic strategies. The synthesized compounds bear rings that are either directly attached to the uracil back bone as in compounds 6, 12a-c and 15, or attached through an amino bridge as compounds 3a-c, 5a, b, 7a, b, 9 and 10, or through an imino bridge as compound 18. Also, compounds 4, 8, 11a-c, 14, 16 and 17 bearing biologically active side chains were synthesized. In addition to, compounds 13, 19, 20, 21 and 22 bear fused rings to the uracil backbone. All synthesized compounds were evaluated for their anticancer activity against prostate PC3 cell line using in-vitro sulforhodamine-B (SRB) method, from which compounds 3a, c, 4, 5a, b, 6, 7a, b, 11a-c, 12a, b, 17 and 20 were the most active. These active compounds were further evaluated for their ability to inhibit cathepsin B enzyme by using enzyme-linked immunosorbent assay, which revealed that compounds 5a, b, 7a, 11a, 12a and 17 exhibited more than 50% inhibition of cathepsin B. Among which the phenyl thiourea derivative 17 was the most active exhibiting 82.3% inhibition, while the reference doxorubicin exerted 18.7% inhibition.展开更多
A case of advanced multiple hepatocellular carcinomas (HCC) with portal vein tumor thrombosis successfully treated by oral tegafur/uracil is reported. A 69-year-old Japanese woman with advanced HCC with tumor thrombos...A case of advanced multiple hepatocellular carcinomas (HCC) with portal vein tumor thrombosis successfully treated by oral tegafur/uracil is reported. A 69-year-old Japanese woman with advanced HCC with tumor thrombosis underwent transcatheter arterial infusion chemotherapy in April 2001. However, 1 year later, the patient experieced a recurrence with advanced multiple HCC with portal vein tumor thrombosis and ascites. Treatment with oral tegafur/uracil was started in May 2002 and resulted in the partial response of liver tumors and the complete improvement of ascites. She remained in good health for about 6 years. This case strongly suggests that oral tegafur/uracil is an effective treatment for some cases of advanced HCC with portal vein tumor thrombosis.展开更多
Background: This study evaluated the tolerability and efficacy of intermittent oxaliplatin treatment based on mFOLFOX6 using oral uracil-tegafur(UFT) and leucovorin(LV) maintenance therapy in the treatment of elderly ...Background: This study evaluated the tolerability and efficacy of intermittent oxaliplatin treatment based on mFOLFOX6 using oral uracil-tegafur(UFT) and leucovorin(LV) maintenance therapy in the treatment of elderly patients with advanced colorectal cancer. Methods: Ten non-elderly patients (70 years) with advanced/recurrent colorectal cancer were enrolled in this prospective, multicenter cooperative group clinical trial. The mFOLFOX6 regimen was administered for eight cycles with maintenance therapy with oral UFT/LV treatment until progression. In cases with disease progression, mFOLFOX6 was reintroduced. Results: Grade 2 peripheral neuropathy was noted in 30.0% and 25.0% of the elderly and non-elderly patients, respectively. The observed time to treatment failure (TTF) was 6.3 months in the elderly patients and 6.4 months in the non-elderly patients. The disease control rate was 83.3% in each group. Conclusion: Our new stop-and-go strategy using oral UFT/LV is well-tolerated and effective even in elderly patients.展开更多
A general method for the solid phase synthesis of hydro-uracils and thiouracils is described. Resino ester 2 reacts with various primary amines to give secondary amines 3, which are converted to the resino ureas (thio...A general method for the solid phase synthesis of hydro-uracils and thiouracils is described. Resino ester 2 reacts with various primary amines to give secondary amines 3, which are converted to the resino ureas (thioureas) 4 by treatment with isocyanates (isothiocyanates). Preparation of the hydro-uracils and thiouracils 5 is achieved by acidic cyclization-cleavage from the resin. The synthesis is designed to be amenable for structure based library approach to photosystem II D1 protein inhibitors.展开更多
基金We thank the National Natural Science Foundation of China(NO.20172007)for financial support
文摘Methyluracil and 5-nitro-6-methyluracil react with variable molar quantities of benzoyl chloride in acetonitrile-pyridine at room temperature to give 1-N, 3-N-dibenzoyl-6- methyluracil 3b and 1-N-benzoyl-5-nitro-6-methyluracil 4b. The reactive rates of debenzoylation of 3b and 4b were investigated.
基金National Science Foundation of China (Grant No.20672)the Doctoral grant of the Ministry of Education of China(Grant No.2007000174).
文摘1-Alkyl-5-amino-6-phenylethyluracils (1a, 1b) were synthesized as potential non-nucleoside HIV-1RT inhibitors. A convenient synthetic procedure was developed for the preparation of 1-alkyl-5-amino or 5-aminosubstituted-6-phenylethyluracils, which were synthesized in three or four steps from 6-methyluracil in good yield. The development of a one-pot reaction that simultaneously removed the benzyl protection group and reduced the nitro group greatly improved the yield of the synthesis. Compounds 1a and 1b are analogs of MKC-442, which is an efficient inhibitor of HIV-1 reverse transcriptase, 1a and 1b were tested for their inhibition of HIV-1RT, and moderate activity was found for 1a.
基金Supported by the National High Technology Research and Development Program of China(No.2006AA02Z108)the National Basic Research Program of China(No.2009CB118906)the National Natural Science Foundation of China(Nos.30700131,30870512)
文摘We report the characterization of a uracil-DNA glycosylase(UDG) from the hyperthermophilic archaea Pyrococcus furiosus(P, furiosus). P. furiosus UDG(PfUDG) has high sequence similarity to the families IV and V UDGs(thermostable UDG family and PaUDG-b family). PfUDG excises uracil from various DNA substrates with the following order: U/T=U/C〉U/G=U/AP=U/-〉U/U=U/I=U/A. The optimal temperature and pH value for uracil exci- sion by PfUDG are 70 ℃ and 9.0, respectively. The removal of U is inhibited by the divalent ions of Fe, Ca, Zn, Cu, Co, Ni and Mn, as well as a high concentration of NaC1. The phosphorothioates near uracil strongly inhibit the exci- sion of uracil by PfUDG. Interestingly, pfuDNA(Pyrococcusfuriosus DNA) polymerase, which tightly binds the ura- cil-carrying oligonucleotide, does not inhibit the excision by Pfl.IDG, suggesting PfUDG in vivo functions as the re- pair enzyme to excise uracil damage in genome.
基金This work was supported by the National Natural Science Foundation of China (No. 20171031)
文摘For the uracil-BX3 (X = F, Cl) systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals (B3LYP) method of density functional theory (DFT) and the second-order Moller-Plesset (MP2) method of ab initio at the 6- 311 +G^* or 6-311 ++G^* basis set. Four isomers were found for each system, and then the single-point energy evaluations were performed using the larger basis sets of (6-311 +G(2df, p) and aug-cc-pVDZ with DFF method. In the most stable isomer of uracil-BF3 or uracil-BCl3, the boron atom of BX3 (X = F, Cl) connects to the carbonyl oxygen O7 of uracil with a stabilization energy of -46.56 or -31.10 kJ/mol at the B3LYP/6-31 1+G^* level (BSSE corrected). The analyses for combining interaction between BX3 and uracil with the atom-in-molecule theory (AIM) and natural bond orbital method (NBO) have been performed. The results indicate that all isomers were formed with σ-p type interactions between uracil and BX3, in which the carbonyl oxygen offers its lone pair electrons to the empty p orbital of boron atom and the concomitances of charge transfer from uracil to BX3 occur. Moreover, there exists one or two hydrogen bonds in most isomers of uracil-BX3 system and these hydrogen bonds contribute to the stability of the complex systems. Frequency analysis suggests that the stretching vibration of BX3 undergoes a red shift in complexes. Uracil-BF3 complex is more stable than uracil-BCl3 although the distance of B-O is shorter in the latter. Besides, the conversion mechanisms between different isomers of uracil-BF3 have been obtained.
文摘One practical and industrial procedure for preparation of 5-hydroxymethyluracil has been developed. This method has the advantage of facile operation, low cost and stable yield.
文摘Background: We evaluated the feasibility and efficacy of irinotecan (CPT-11) plus tegafur/uracil (UFT) combination chemotherapy in patients with advanced colorectal cancer. Patients and Methods: PK parameters were concurrently measured to confirm the presence of drug interactions in this treatment schedule. CPT-11 was administered intravenously at the dose of 150 mg/m2 on days 1, 15. UFT was administered at the dose of 375 mg/m2/day (B.I.D.) on days 3 - 7, 10 - 14, 17 - 21, 24 - 28 repeated every 5 weeks. Results: 31 patients were enrolled. PK parameters for CPT-11, FT, 5-FU and uracil are available from 5 patients. The overall response rate was 16.1%. The median time to treatment discontinuation was 3.9 months. There was no significant difference in PK parameters of CPT-11 between day 1 and day 15 and of UFT between day 3 and day 10. Conclusion: CPT-11 plus UFT combination chemotherapy exhibited a tolerable toxicity profile with acceptable efficacy. Pharmacokinetic analysis showed that there were no drug interactions in this treatment schedule.
文摘A new series of compounds, 1-[(O,O-diphenyl phosphonyl)arylmethylene aminocarbonylmethyl]uracils, were synthesized in yield of 54.6-72.0% with DCC/BtOH as the coupling reagent, and their biological activities are being tested.
文摘Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, including Japan. Although the development of imaging modalities has made the early diagnosis of HCC possible, surgically resectable cases are relatively uncommon because of hepatic function reserve and/or an advanced stage at presentation. Several modalities, such as transcatheter arterial chemoembolization, percutaneous ethanol injection, microwave coagulation therapy and radiofrequency ablation are reportedly useful in treating patients with non-resectable disease. However, unfortunately, many HCC patients have tumor recurrence. The overall prognosis of patients with HCC is very poor, and treatment of the advanced form is still problematic. In this article, we review the clinical efficacy and toxicity of enteric-coated tegafur/uracil in the treatment of patients with advanced non-resectable HCC.
文摘Tegafur-uracil has been reported to have only minor adverse effects and is associated with liver injury in 1.79% of Japanese patients. The development of tegafur-uracil-induced hepatic fibrosis with portal hypertension is rare. Here, we report a case of a 74-year-old woman with rapidly developing tegafururacil-induced hepatic fibrosis. The patient had no history of liver disease and had been treated with tegafur-uracil for 8 mo after breast cancer surgery. The patient was admitted to our hospital for abdominal distension and leg edema associated with liver dysfunction. Computed tomography imaging revealed massive ascites and splenomegaly, and a non-invasive assessment of liver fibrosis indicated advanced fibrosis. The histopathological findings revealed periportal fibrosis and bridging fibrosis with septation. The massive ascites resolved after discontinuing tegafururacil. These findings suggest that advanced hepatic fibrosis can develop from a relatively short-term administration of tegafur-uracil and that non-invasive assessment is useful for predicting hepatic fibrosis.
文摘Michael addition reactions of uracil to acrylates were catalyzed by an alkaline protease from Bacillus subtilis in dimethyl sulfoxide at 55 ℃ for 72 h. The adducts were determined by TLC, IR and 1H NMR.
文摘The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N- methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final product was obtained in 20.8% yield.
文摘The photolysis of uracil in phosphate-buffered saline (PBS, pH 8.0) under the irradiation pf medium pressure mercury lamp (MPML) leads to the production of a novel compound C4H5N2O6P. The composition and structure of the compound has been identified by elemental analysis, EI-MS, UV, IR, H-1, C-13, P-31-NMR.
文摘6-aminouracil 1 was utilized to introduce different heterocyclic rings at C-6 position through various synthetic strategies. The synthesized compounds bear rings that are either directly attached to the uracil back bone as in compounds 6, 12a-c and 15, or attached through an amino bridge as compounds 3a-c, 5a, b, 7a, b, 9 and 10, or through an imino bridge as compound 18. Also, compounds 4, 8, 11a-c, 14, 16 and 17 bearing biologically active side chains were synthesized. In addition to, compounds 13, 19, 20, 21 and 22 bear fused rings to the uracil backbone. All synthesized compounds were evaluated for their anticancer activity against prostate PC3 cell line using in-vitro sulforhodamine-B (SRB) method, from which compounds 3a, c, 4, 5a, b, 6, 7a, b, 11a-c, 12a, b, 17 and 20 were the most active. These active compounds were further evaluated for their ability to inhibit cathepsin B enzyme by using enzyme-linked immunosorbent assay, which revealed that compounds 5a, b, 7a, 11a, 12a and 17 exhibited more than 50% inhibition of cathepsin B. Among which the phenyl thiourea derivative 17 was the most active exhibiting 82.3% inhibition, while the reference doxorubicin exerted 18.7% inhibition.
文摘A case of advanced multiple hepatocellular carcinomas (HCC) with portal vein tumor thrombosis successfully treated by oral tegafur/uracil is reported. A 69-year-old Japanese woman with advanced HCC with tumor thrombosis underwent transcatheter arterial infusion chemotherapy in April 2001. However, 1 year later, the patient experieced a recurrence with advanced multiple HCC with portal vein tumor thrombosis and ascites. Treatment with oral tegafur/uracil was started in May 2002 and resulted in the partial response of liver tumors and the complete improvement of ascites. She remained in good health for about 6 years. This case strongly suggests that oral tegafur/uracil is an effective treatment for some cases of advanced HCC with portal vein tumor thrombosis.
文摘Background: This study evaluated the tolerability and efficacy of intermittent oxaliplatin treatment based on mFOLFOX6 using oral uracil-tegafur(UFT) and leucovorin(LV) maintenance therapy in the treatment of elderly patients with advanced colorectal cancer. Methods: Ten non-elderly patients (70 years) with advanced/recurrent colorectal cancer were enrolled in this prospective, multicenter cooperative group clinical trial. The mFOLFOX6 regimen was administered for eight cycles with maintenance therapy with oral UFT/LV treatment until progression. In cases with disease progression, mFOLFOX6 was reintroduced. Results: Grade 2 peripheral neuropathy was noted in 30.0% and 25.0% of the elderly and non-elderly patients, respectively. The observed time to treatment failure (TTF) was 6.3 months in the elderly patients and 6.4 months in the non-elderly patients. The disease control rate was 83.3% in each group. Conclusion: Our new stop-and-go strategy using oral UFT/LV is well-tolerated and effective even in elderly patients.
文摘A general method for the solid phase synthesis of hydro-uracils and thiouracils is described. Resino ester 2 reacts with various primary amines to give secondary amines 3, which are converted to the resino ureas (thioureas) 4 by treatment with isocyanates (isothiocyanates). Preparation of the hydro-uracils and thiouracils 5 is achieved by acidic cyclization-cleavage from the resin. The synthesis is designed to be amenable for structure based library approach to photosystem II D1 protein inhibitors.