3-(3-Pyridinyl)-7-(indol-3-ylcarbonyl)-1H-3H-pyrrolo[1,2-c] thiazoles represent a class of potent, orally active PAF antagonists; however, the lead compounds in this series suffered from a lack of aqueous solubility. To overcome this limitation, a number of strategies were examined to achieve improved solubility, involving the incorporation of polar substituents and the use of prodrugs.