3-Arabinoside

Antiviral Agents. Although a number of antibiotics have been shown to have some sort of antiviral activity, only vidarabine [5536-17-4] (adenine arabinoside) is used clinically against viral infections at this time. As the need for new antiviral agents (qv) increases and new screening procedures are developed, one would expect the discovery of other new effective antiviral antibiotics that could be used safely in human therapy. 

Chemotherapeutic agents are grouped by cytotoxic mechanism. The alkylating agents, such as cyclophosphamide [50-18-0] and melphalan [148-82-3] interfere with normal cellular activity by alkylation deoxyribonucleic acid (DNA). Antimetabohtes, interfering with complex metaboHc pathways in the cell, include methotrexate [59-05-2] 5-fluorouracil [51-21-8] and cytosine arabinoside hydrochloride [69-74-9]. Antibiotics such as bleomycin [11056-06-7] and doxombicin [23214-92-8] h.a.ve been used, as have the plant alkaloids vincristine [57-22-7] and vinblastine [865-21-4]. 

Fig. 1 Chromatography of flavonoids. 1. Extract. Solidaginis 2. Rutin — chlorogenic acid — isoquercitrin — quercitrin 3. Extract. Hyperici 4. Hyp>erosid — quercetin-3-arabinosid — hypericin — quercetin 5. Extract. Betulae...

Chemical Name 4-amino-1(3-D-arabinofuranosyl-2(1H)-pyrimidinone hydrochloride Common Name (3-cytosine arabinoside Structural Formula ... 

The drug is metabolized rapidly in the liver, kidney, intestinal mucosa, and even red blood cells. Therefore it has a plasma half-life of only 10 min after bolus intravenous application. The major metabolite, uracil arabinoside (ara-U), can be detected in the blood shortly after cytarabine administration. About 80% of the dose is excreted in the urine within 24 h, with less than 10% appearing as cytarabine the remainder is ara-U. After continuous infusion, cytarabine levels in the liquor (cerebro-spinal fluid) approach 40% of that in plasma. Continuous infusion schedules allow maximal efficiency, with uptake peaks of 5-7 pM. It can be administered intrathecally as an alternative to methotrexate. 

HBV infection remains a major worldwide public health problem. The World Health Organization estimates that there are still 350 million chronic carriers of the vims, who are at risk of developing chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. The success of IFN-a treatment - mainly performed as combined treatment with adenine-arabinoside - has been measured by the normalization of liver enzymes, loss of HBe antigen and of detectable viral DNA in the serum of patients. It has been estimated from several clinical trials that as many as 40% of treated HBV patients would respond to therapy with IFN-a or combined treatment with nucleoside analogues and IFN-a. 

The following fiRf values were obtained quercetin 90 — 95, hypericin 75 — 80, quercitrin 60 — 65, quercetin-3-arabinoside 55 — 60, isoquercitrin 45 — 50, hyperoside 40—45, chlorogenic acid 30 — 35, rutin 20—25 (Fig. 1). 

Intraperitoneal administration of chemotherapeutic agents has been used for many years as a way of increasing the delivery of drugs to tumors (e.g., ovarian carcinoma) located in the peritoneal cavity (Markman, 1986 Howell and Zimra, 1988). Cisplatin (Casper et al., 1983 Markman et al., 1985), cytosine arabinoside (Ara-C) (King et al., 1984 Markman et al., 1985, 1986), and bleomycin (Markman et al., 1986) are examples of intraperitoneally administered drugs which were already successfully applied in clinical settings. 

Hunt, C. A., Rustum, Y. M., Mayhew, E., and Papahadjopoulos, D. (1979). Retention of cytosine arabinoside in mouse lung following intravenous administration in liposomes of different size, Drug Metabol. Dispos., 7, 124-128. 

Juliano, R. L., and Me Cullough, H. N. (1980). Controlled delivery of an antitumor drug Localized action of liposome encapsulated cytosine arabinoside administered via the respiratory system, J. Pharmacol. Exp. Ther., 214, 381-387. 

King, M. E, Pfeifle, C. E., and Howell, S. B. (1984). Intraperito-neal cytosine arabinoside therapy in ovarian carcinoma, J. Clin. Oncol.. 2, 662-669. 

Mayhew, E., Rustum, Y. M., and Szoka, F. (1982). Therapeutic efficacy of cytosine arabinoside trapped in liposomes, in Targeting of Drugs (G. Gregoriadis, J. Senior, and A. TTOuet, eds.). Plenum Press, New York, pp. 249-260. 

Fig. 7.—Predicted (- -) and Fragment (—) Circular Dichroism Spectra /3-L-Arabinose Calculated from (a) a-D-Xylose, and (b) Methyl /3-L-Aiabinoside a-L-Arabinose Calculated from (c) j3-D-Xylose, and (d) Average Calculated for /3-L-Arabinose Methyl a-L-Arabinoside Calculated from (e) Methyl /3-D-Xyloside, and (f) Methyl /3-L-Arabinoside. (Redrawn from Ref. 6.)...

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