Antitumor properties

One area of research is the replacement of sulfur with selenium to enhance the potency of organic compounds in pharmaceutical apphcations. This has seldom been successflil and often the toxicity is increased. There are some exceptions, eg, selenazofurin, phenylaminoethyl selenide, ebselen, and selenotifen (64). Selenazofurin is a cytotoxic compound having antitumor properties, phenyl aminoethyl selenide is used to reduce hypertension, ebselen inhibits a variety of inflammatory and tissue damaging reactions, and selenotifen is an antiallergic agent. 

Caracemide (3) is an antitumor agent. This simple molecule is constructed by reacting acetohydroxamic acid (1) with methylisocyanate (2) promoted by triethylamine. The resulting 0,N-biscarbamate (3), caracemide, is metabolized readily either by deacetylation or by decarba-moylation and its antitumor properties are believed to re.sult from the reactivity of the resulting metabolites with DNA [1]. 

Rhodium, pentakis(trialkyl phosphite), 4, 929 Rhodium, tetrakis(acetato)di-antitumor properties, 4,936 ozonization, 4, 951... 

SEKINE K, OHTA J, ONIS M, TATSUKI T, SHIMOKAWA Y, TOIDA T, KAWASHIM T, HASHIMOTO Y (1995) Analysis of antitumor properties of effecter cells stimulated with a cell wall preparation (WPG) of Bifidobacterium infantis. Biol Pharm Bull. 18 148-53. 

Antitumor properties of some 2-[(dimethylamino)methyl]phenyl-gold(lll) complexes./oumoi of Medicinal Chemistry, 39, 5208. 

Although both nuclear and extranuclear alkoxy- and aryloxyquinoxalines are easily made, only the nuclear ethers can be used as substrates for nucleophilic displacements. Some acyloxy- and trialkylsiloxyquinoxalines are also covered briefly in this section. Many substituted phenoxyquinoxalines1104 and analogs1085 show antitumor properties. 

Isoquino[2,l-d[l,3,2]benzodiazaphosphorine derivatives were found to possess antitumor properties <2000PS(162)>. 

A more complex structure is that of leinamycin 45 (Scheme 15), a material with potent cytotoxic and antitumor properties, isolated from a Streptomyces sp. A 1,2 dithiolane-3-one ring is spiro fused to a complex macrolactam96 (and references therein). Leinamycin has the remarkable ability to cleave DNA. In brief, leinamycin reacts with a thiol and, after a profound rearrangement, forms an episulfonium ion. This ion alkylates the N7 position of guanosine residues in double stranded DNA an unstable adduct is depurinated by hydrolysis of the glycosidic bond between the alkylated base and a deoxyribose residue. Some structurally less complex l,2-dithiolane-3-one 1-oxides have a similar DNA cleaving ability.97... 

Pyrrole Natural Products with Antitumor Properties... 

Although a-carbolines (in particular, 2-amino-a-carboline) are perhaps better known as mutagens [89], some a-carbolines have been found to possess antitumor properties. For example, there has been much interest in the synthesis of natural products grossularine-1 133 and grossularine-2 134 (Fig. 38) since the report of their activity as antitumor agents at the 10 ng/mL level [90]. 

Gupton JT (2006) Pyrrole Natural Products with Antitumor Properties. 2 53-92... 

A number of reports, both old and recent, describe antiviral, antimicrobial, an-tiparasitic, and antitumoral properties of a number of furoxan derivatives [7, 11, 12]. Since it is known that nitric oxide displays potent cytotoxic actions in the immune... 

A rich family of intensely blue-coloured, linear platinum complexes, called platinum blues , has received a great body of attention in the years from 1970 to 1990, not only for their unusual physico-chemical properties, but also for their antitumor properties.14... 

The vinblastine alkaloids are important chemotherapeutic materials, and are well known for their antitumor properties. A two-electron oxidation of alkaloid cantha-ranthine (125) followed by nucleophilic capture of the resulting imminium ion (126) by Cio of vindoline (127), afforded (128) and provided access to this important class of materials (Scheme 29) [56]. 

Drummond DC, Marx C, Guo Z, et al. Enhanced pharmacodynamic and antitumor properties of a histone deacetylase inhibitor encapsulated in liposomes or ErbB2-targeted immunoliposomes. Clin Cancer Res 2005 11 3392-3401. Mamot C, Drummond Dc, Noble CO, et al. Epledermal growth factor receptor-targeted immunoliposomes significantly enhance the efficacy of multiple anticancer drugsin vivo. Cancer Res 2005 65 1631-1638. 

The primary clinical application of the antiproliferative effects of the bisindole alkaloids has been in the treatment of human neoplasms. A variety of experimental antitumor systems have been used to study the antitumor properties of these alkaloids in animal models, and much of the information presented for specific compounds in this chapter highlights these effects. Early studies employed syngeneic mice bearing hematopoietic... 

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