Two persons were sentenced to jail yesterday, two others received probation and another was forced to continue serving a four-month sentence in connection with fraud-related cases in U.S. court here.

The two who received probation would have been sent to jail, said the sentencing judge, except for their continued cooperation with prosecutors in an extensive credit fraud investigation here.

Yesterday's actions were the latest examples of a trend in the federal court here to deal more severly with so-called white-collar criminals.Four of the five cases yesterday came before U.S. Senior District Judge William B. Jones, who has in the past two years sent to prison practically all the white-collar defendants who have come before him.

Three of the cases before Jones yesterday involved a massive scheme to launder adverse credit ratings of hundreds of persons. Two other persons who have been charged in that continuing investigation will be sentenced today.

Jones yesterday placed two employees of the Credit Bureau Inc., on five years probation for their guilty pleas in connection with the credit scheme. The two men, who said they would alter the credit records of persons at the direction of someone outside the firm, assured Judge Jones that they had cooperated fully wit the investigation and would testify at trials of persons who expected to be charged in the future.

Receiving the probation terms were Roberta Vaughan, 27, of 2104 D St, SE, who had been a surpervisor of computer operations for the Credit Bureau, and Rosalyn Cleo Jordan, 30, of 1370 Oak St.NW, who also worked there.

Former boxer Robert (BoBo) Renfrow, 27, of 6003 Clay St. NE, did not fare as well. Judge Jones sentenced the 280 pound Renfrow to serve 6-to-18 months in jail in connection with his altering of his own credit files when he was a car salesman.

Later in the day, Jones refused to reduce the sentence of a 44-year-old woman who failed to report and pay income taxes on $40,000 she earned as a practical nurse over a four-year period.

Her attorney, Harry T.Alexander, said he was appealing the four-month sentences in the past for similar crimes.

Jones abruptly blocked Alexander, a former Superior Court judge from explaining his appeal further, called it frivolous and ordered Mrs. Wright to return to jail.

Mrs. Wright's husband, who makes $19,000 a year with the D.C. school system, was in the courtroom. They are the parents of five children, ranging in age from 8 to 22.

Assistant U.S. Attornsy Robert W. Orgen of the fraud division said Jones' sentence was consistent with others imposed by federal judges in tax cases here.

The fifth fraud-related case yesterday involved Richard J. Sheppard, 30, of 4660 Martin Luther KIng Ave. SE, who pleaded guilty to defrauding 25 credit card companies over a 15-month period.

U.S. District Judge John Lewis Smith Jr. sentenced Sheppard to one-to-three years in prison for his guilty plea, saying such a sentence was necessary to deter others from attempting similar credit card fraud schemes, Sheppard said at his plea that he would apply for the cards and receive them by supplying the companies with false information about his salary.