Actinomycin D

Actinomycin D is a polypeptide antibiotic first described by Waksman. It is bacteriostatic in nature, especially towards gram negative bacteria. Actinomycin D was the first antibiotic shown to have anti-cancer activity.
Actinomycin is a clear, yellow liquid administered intravenously and most commonly used in treatment of a variety of cancers. It is also used as a radiosensitizer in adjunct to radiotherapies, since it can increase the radiosensitivity of tumor cells by inhibiting repair of sublethal radiation damage and delay the onset of the compensatory hyperplasia that occurs following irradiation.
In cell biology, actinomycin D is shown to have the ability to inhibit transcription. Actinomycin D does tAhis by binding DNA at the transcription initiation complex and preventing elongation of RNA chain by RNA polymerase. 
Prepare a solution of 1 mg actinomycin D (Sigma-Aldrich A1410) in 816 µ L of DMSO. Determine the exact concentration of stock actinomycin D by measuring the absorbance at 441 nm and applying Beers law. Actinomycin D has a molar extinction coefficient of 21, 900 (in water). The light path will depend on the spectrophotometer used to measure the absorbance at 441 nm. This is generally 1 cm when using older-style machines with cuvettes, but can be shorter (< 1 mm) in modern machines such as the NanoDrop.

8-AMINO-N-(2-AMINO-4, 6-DIMETHYL-3-OXO-PHENOXAZIN-1-YL)CARBONYL-N'-[8-AMINO-4, 6-DIMETHYL-7-OXO-9-[[3, 6, 10-TRIMETHYL-7, 14-BIS(1-METHYLETHYL)-2, 5, 8, 12, 15-PENTAOXO-9-OXA-3, 6, 13, 16-TETRAZABICYCLO[14.3.0]NONADEC-11-YL]CARBAMOYL]PHENOXAZIN-1-YL]CARBONYL-4, 6-DIME

251 - 252° C

0, 98

Red to orange Powder

X1005390-0

C₆₂H₈₆N₁₂O₁₆

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