Isatin 2-thiosemicarbazones

Y-(Dialkylaminomethyl)isatin-/ -thiosemicarbazones were apparently not active against polio and influenza at non-toxic doses [168], and indane-1,3-dione bis-alkylthiosemicarbazones claimed to be active against polio were the subject of another very poorly detailed paper [169]. [Pg.141]

Thlosemicarbazones - No clinical experiments utilizing isatin thiosemicarbazones in poxvirus infections were reported during this period. The finding that isatin thiosemicarbazones active against poxvirus also inhibit the multiplication of certain strains of rhinovirus led to the finding that 2-methyl-4 5-tnethyl-5H-as-triazino- indol-5-yl)amin5 -2-... [Pg.102]

Virus replication comprises numerous biochemieal transformations that might provide suitable targets for antiviral therapy. The antiviral effect of thiosemicarbazones was first demonstrated by Hamre et al. [53, 54], who showed that p-aminobenzaldehyde-3-thiosemicarbazone and several of its derivatives were active against vaccinia virus in mice. These studies were extended to include thiosemicarbazones of isatin, benzene, thiophene, pyridine, and quinoline derivatives, which also showed activity against vaccinia-induced encephalitis. The nature of the aldehyde/ketone moiety was not as significant as the presence of the thiosemicarbazide side chain the latter was deemed essential for antiviral activity. [Pg.7]

A novel ring contraction of 6-azauraciIs yields imidazole derivatives . Azauracil-5-yl-isatin 33 is converted through its thiosemicarbazone 34 to 6-(6-azauracil-5-... [Pg.300]

Isatin reacts with formaldehyde and a variety of amines in the Mannich reaction to give compounds of type 42.181-193a A similar reaction takes place with isatin-3-thiosemicarbazone,185,187 or 42 can react with thiosemicarbazide to give a similar product.192 In the absence of an amine, isatin181 and substituted isatins157,193a with form-... [Pg.14]

Isatin-3-hydrazones react with aldehydes to give 91.157,314 Compound 91 (R = H, Ar = 2-(5-nitrofuryl)) has also been prepared by reaction of isatin with 5-nitrofurfuraldehyde hydrazone.314 Ammonium isothiocyanate, and 86 gave isatin-3-thiosemicarbazones.318... [Pg.28]

A very large variety of isatins reacted with thiosemicarbazides to give isatin-3-thiosemicarbazones (98).29 58,146,151,155 156,166,181,182,192,193a,2°0, 304.312.315.326-344 rp te impetus for the bulk of this work is the fact... [Pg.30]

An excess of isatin with thiocarbohydrazide gives 106.384 The syn isomer of isatin-3-thiosemicarbazone predominates while isatin-3-semicarbazone exists in the anti form.305 Treatment with acid or warming converts this anti form into the syn isomer, while base causes the reverse isomerization.344 4-Methylisatin-3-semicarbazone exists as the syn isomer.344... [Pg.33]

A number of cyclization reactions have been carried out with isatin derivatives of this series. Isatin-3-thiosemicarbazone with chloroacetic acid, sodium acetate, acetic acid, and aldehydes gave 107.392,393... [Pg.33]

A-methylisatin-3-semicarbazone could be cyclized to the oxo analog of 108,399 but the cyclization of the thiosemicarbazone to 108 occurred much more easily.400 Similar treatment of isatin-3-semicarbazone led to 113 via ring opening of the isatin.400 In the A-acetyl series (98, R =... [Pg.34]

The cyclization of certain 2-substituted isatin derivatives were studied so as to compare them with the above cyclizations. Thus, isatin- 2-thiosemicarbazone (126) and isatin-2-semicarbazone (127) underwent cyclization to 128 and 129 more easily than the corresponding cyclizations in the 3-series.406 As in the 3-series the sulfur compound underwent cyclization more easily than the oxygen.408 In contrast to... [Pg.36]

Isatin j8-thiosemicarbazones (97) readily give triazinoindoles (98) (72JMC277). Deprotonation of the amide (99) leads to ring closure on to the urethane carbonyl group to give (100). In a similar reaction (101 to 102) the lower reactivity of the t-butyl ester induces ring closure in the required direction (78CPB3080). [Pg.515]

Among biologically active compounds - derivatives of isatin - there is methisazone (1-methylisatin 3-thiosemicarbazone), which has been used as a prophylactic agent against the smallpox virus [139-141], Methods for the synthesis of compounds with the general formula 146 have been developed in the search for new antiviral and antimicrobial agents [142] ... [Pg.24]

The stereochemistry of isatin-3-thiosemicarbazone-5-sulfonate was studied in aqueous solution, and in acidic pH the Z isomer was determined to be the most stable, but after... [Pg.45]

Isatin hydrazones and thiosemicarbazones can also be used as substrates for the Mannich reaction, leading to functionalization at N- . Isatin-3-hydrazone reacts with 1,1-... [Pg.45]

Tomchin and coworkers also described that O-methyli satin reacts with thiosemicarbazine to furnish isatin-2-thiosemicarbazone, which can undergo a cyclization reaction under acidic conditions to furnish a thiadiazanoindole derivative the kinetics of the reaction were subsequently determined. Later, Tomchin also described that isatin-2-thiosemicarbazones suffer a cleavage reaction of the five member ring, and the intermediate formed recyclizes to a thiadiazole derivative (Scheme 58). [Pg.47]

Isatin-2,3-thiosemicarbazone is said to be produced only from isatin-2-thiosemicarbazone and thiosemicarbazine direct reaction of isatin with an excess of thiosemicarbazine gives only the C-3 substituted oxindole. The isatin-2,3-thiosemicarbazone cyclizes to a thiotriazinoindole derivative when heated280 (Scheme 59). [Pg.48]

Isatin-3-thiosemicarbazones are useful substrates for the synthesis of other 3-... [Pg.48]

Due to its ability to bind ferric ions, isatin-3-thiosemicarbazone can be used to form magneto-polymer composites with poly (vinyl chloride)... [Pg.98]

The thiosemicarbazone of 7-azaisatin lacked antiviral activity isatin and pyridinecarboxaldehyde derivatives are active. ... [Pg.104]

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