A federal grand jury in Washington has indicted two Maryland men on charges of running a ring to obtain prescriptions for Dilaudid, a synthetic form of morphine, and selling them for more than $37,000 to wholesalers who then distributed the drugs on the street.

One of the men named in the indictment--unsealed yesterday--is William Dudley, 48, of Landover, who was indicted in Baltimore last March with Maryland State Sen. Tommie Broadwater Jr. and two others on charges of buying illegally obtained food stamps and redeeming them through Broadwater's supermarket. All four men in that case have denied the charges.

In a hearing yesterday before U.S. District Judge Thomas Penfield Jackson, Dudley and his brother, Alwyn Matthews, of Silver Spring, pleaded not guilty.

Jackson ordered Dudley, described in the indictment as the "organizer, supervisor and manager" of the scheme, held on $250,000 bond. Jackson ordered Matthews released on a $5,000 unsecured bond pending trial for both men on Sept. 12. Both men were arrested yesterday by U.S. Secret Service agents and agents of the Department of Agriculture.

According to the indictment, Dudley and Matthews sent four other persons--all of whom were named as unindicted coconspirators--to an area physician not charged in the case to get prescriptions, generally for about 50 tablets.

Assistant U.S. Attorney Douglas J. Behr told Jackson that Dudley then allegedly sold the drugs, which cost about 40 cents apiece at drugstores, for about $17 each to others who distributed them on the streets for about $35 a pill.

Behr said the alleged sales by Dudley from late December to early March came to about $37,000.

Both men are charged with conspiracy to possess and possession of a controlled substance with intent to distribute, as well as several other counts. If convicted of the charges, Matthews faces up to 15 years in prison on each of eight counts in the indictment. Dudley also faces 15 years for each of 16 counts against him and a mandatory minimum without parole of 10 years in prison on an additional count of operating a continuing criminal enterprise.