ChemInform Abstract: A Practical Method to Cleave Diphenyl Phosphonate Esters to Their Corresponding Phosphonic Acids in One Step.

ChemInform ◽  
2009 ◽  
Vol 40 (45) ◽  
Author(s):  
Bo-Seung Kim ◽  
Beom-Tae Kim ◽  
Ki-Jun Hwang
2020 ◽  
Vol 17 (8) ◽  
pp. 628-630
Author(s):  
Vu Binh Duong ◽  
Pham Van Hien ◽  
Tran Thai Ngoc ◽  
Phan Dinh Chau ◽  
Tran Khac Vu

A simple and practical method for the synthesis on a large scale of altretamine (1), a wellknown antitumor drug, has been successfully developed. The synthesis method involves the conversion of cyanuric chloride (2) into altretamine (1) by dimethylamination of 2 with an aqueous solution of 40% dimethylamine and potassium hydroxide in 1, -dioxan 4in one step to give altretamine (1) in high yield.


Organics ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 107-117
Author(s):  
Mattia Forchetta ◽  
Valeria Conte ◽  
Giulia Fiorani ◽  
Pierluca Galloni ◽  
Federica Sabuzi

Owing to the attractiveness of organic phosphonic acids and esters in the pharmacological field and in the functionalization of conductive metal-oxides, the research of effective synthetic protocols is pivotal. Among the others, ω-bromoalkylphosphonates are gaining particular attention because they are useful building blocks for the tailored functionalization of complex organic molecules. Hence, in this work, the optimization of Michaelis–Arbuzov reaction conditions for ω-bromoalkylphosphonates has been performed, to improve process sustainability while maintaining good yields. Synthesized ω-bromoalkylphosphonates have been successfully adopted for the synthesis of new KuQuinone phosphonate esters and, by hydrolysis, phosphonic acid KuQuinone derivatives have been obtained for the first time. Considering the high affinity with metal-oxides, KuQuinones bearing phosphonic acid terminal groups are promising candidates for biomedical and photo(electro)chemical applications.


2007 ◽  
Vol 72 (7) ◽  
pp. 927-951 ◽  
Author(s):  
Marcela Krečmerová ◽  
Antonín Holý ◽  
Milena Masojídková

NH2-protected 5-phenylcytosine and its derivatives 2a-2d were treated with (2S)-2-[(trityloxy)methyl]oxirane (3) followed by etherification with diisopropyl [(tosyloxy)methyl]phosphonate (5) in the presence of sodium hydride. The intermediary phosphonate esters 6 were debenzoylated and subsequently transformed to free phosphonic acids, i.e. (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-phenylcytosine (5-phenyl-HPMPC) derivatives (8a-8d) by the action of bromotrimethylsilane and subsequent hydrolysis. Deamination of these compounds with 3-methylbutyl nitrite afforded corresponding (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-phenyluracil (5-phenyl-HPMPU) derivatives (9a-9d). R-Enantiomers 14 and 15 were prepared analogously starting from (2R)-2-[(trityloxy)methyl]oxirane. 5-Benzyl-, 5-[(1-naphthyl)methyl]- and 5-[(2-naphthyl)methyl]HPMPU (24a-24c) and -HPMPC (25a-25c) were synthesized from appropriate 5-arylmethyl-4-methoxypyrimidin-2(1H)-ones similarly as described for 5-phenyl derivatives. Antiviral activity was found for (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-phenyluracil (9a) (HSV-1 and HSV-2) and (R)-1-[3-hydroxy2-(phosphonomethoxy)propyl]-5-phenylcytosine (14) (cytomegalovirus and varicella-zoster virus), both tested in cell cultures. Some of the 5-phenyluracil derivatives possessed inhibitory activity against thymidine phosphorylase from SD-lymphoma.


2013 ◽  
Vol 690-693 ◽  
pp. 2982-2989
Author(s):  
Zhi Wei Huang ◽  
Yuan Yuan Wan ◽  
Yan Bin Wang ◽  
Lu Chang Che ◽  
Chuan Lin Liu ◽  
...  

In this paper, an electromagnetic shell part was studied with the design of die, simulation and the flow control forming (FCF) method. The important technology of FCF was the design of cavity die to control metal flow. The simulation results indicate that pyramidal faces of cavity die exerted a significant influence on qualities of parts. The simulation results also revealed that the effective stresses of the sheet were inhomogeneous and the distributions of the equivalent stress were lamellar with obvious gradients. Experimental results show that steel sheet (08Al) could be formed in one step into intricate shapes at room temperature. This confirmed that FCF is a safe, clean and practical method for the near net forming of parts.


2020 ◽  
Vol 16 ◽  
pp. 1436-1446 ◽  
Author(s):  
Katarzyna Justyna ◽  
Joanna Małolepsza ◽  
Damian Kusy ◽  
Waldemar Maniukiewicz ◽  
Katarzyna M Błażewska

The McKenna reaction is a well-known and popular method for the efficient and mild synthesis of organophosphorus acids. Bromotrimethylsilane (BTMS) is the main reagent in this reaction, which transforms dialkyl phosphonate esters into bis(trimethylsilyl)esters, which are then easily converted into the target acids. However, the versatile character of the McKenna reaction is not always used to its full extent, due to formation of side products. Herein, demonstrated by using model examples we have not only analyzed the typical side processes accompanying the McKenna reaction, but also uncovered new ones. Further, we discovered that some commonly recommended precautions did not always circumvent the side reactions. The proposed results and recommendations may facilitate the synthesis of phosphonic acids.


1977 ◽  
Vol 5 (2) ◽  
pp. 178-183
Author(s):  
K J Ryan ◽  
S F Mihalyi

The Aerotest sampler (Olympic Medical Corp., Seattle, Wash.) is designed to detect bacterial contamination of respirator-generated aerosols in a simple one-step process. The sampler was evaluated by controlled contamination of Bennett AP-5, PR-2, and MA-1 respirators with Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter. Bacteria present as viable 1.4 to 3.5-mum particles in each of 77 aerosols were quantitated by using the Andersen viable-particle sampler, and the results were compared with those of colonies obtained from 10-s or 15-cycle Aerotest samples. All aerosols containing counts greater than expected in hospital air were detected by the Aerotest method. Thirteen of 14 aerosols containing less than 20 bacteria/0.028 m3 showed fewer than 5 colonies, whereas all aerosols containing greater than 1,000 bacteria/0.028 m3 showed at least 40 colonies. Aerosols with intermediate counts fell in between. Under the conditions described here, the Aerotest sampler was able to discriminate between the low levels of bacteria commonly found in hospital air and the bacterial contamination associated with nosocomial pneumonia. The Aerotest sampler provides a practical method for surveillance sampling of respirator nebulizers.


2006 ◽  
Vol 71 (4) ◽  
pp. 579-594 ◽  
Author(s):  
Marcela Krečmerová ◽  
Milena Masojídková ◽  
Antonín Holý

1-[(S)-3-Hydroxy-2-(phosphonomethoxy)propyl]cytosine (HPMPC, cidofovir) was modified by substitution on the base moiety in positions C-5 and N4. Key intermediates of these syntheses, diisopropyl esters of (S)-1-[2-(phosphonomethoxy)-3-(triphenylmethoxy)propyl]-5-alkylcytosines (6 and 7) prepared from 5-alkyl-4-methoxypyrimidin-2(1H)-ones were transformed to the corresponding 5-substituted cytosine or N4-alkylcytosine derivatives by the action of ammonia or primary amines, respectively. These fully protected phosphonate esters gave by treatment with bromotrimethylsilane followed by hydrolysis free phosphonic acids: 1-[(S)-3-hydroxy-2-(phosphonomethoxy)propyl]-5-methylcytosine (5-methyl-HPMPC, 10), 5-ethyl-1-[(S)-3-hydroxy-2-(phosphonomethoxy)propyl]cytosine (5-ethyl-HPMPC, 11) and a series of 5-ethyl-HPMPC analogues 17-21 bearing various substituents in N4 position (cyclopropyl, cyclopentyl, 2-hydroxyethyl, allyl, 2-(dimethylamino)ethyl). 5-Ethynyl-1-[(S)-3-hydroxy-2-(phosphonomethoxy)propyl]cytosine (5-ethynyl-HPMPC, 26) was prepared from 5-iodocytosine derivative 23 using Sonogashira coupling with (trimethylsilyl)acetylene, CuI and [PdCl2(Ph3P)2]. None of the prepared compounds exhibited antiviral activity in vitro.


2017 ◽  
Vol 19 (23) ◽  
pp. 5591-5598 ◽  
Author(s):  
Xing Liu ◽  
Min Liu ◽  
Wan Xu ◽  
Meng-Tian Zeng ◽  
Hui Zhu ◽  
...  

An efficient and practical method for the one-step synthesis of benzothiazole-2-thiols, benzoxazole-2-thiols and benzimidazoline-2-thiones in water was described.


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