Guillermo Ungo, Longtime Head Of Salvador Democratic Left, 59

Guillermo Ungo, a longtime leader of the democratic left in El Salvador, died yesterday at the Spanish Hospital in Mexico City. He was 59 years old and lived in San Salvador.

He died of a heart attack, his wife, Nora Lopez Andreu de Ungo, told The Associated Press. On Wednesday, Mr. Ungo underwent a third operation since he was hospitalized on Jan. 11 with a brain tumor and did not regain consciousness. His wife said his body would be returned to El Salvador tomorrow.

Mr. Ungo was for many years the secretary general of the National Revolutionary Movement, which sought to bring about peaceful change in a country caught in conflict between Marxist guerrillas and conservative forces. In 1979 and 1980 he served on a junta that governed El Salvador and was an unsuccessful presidential candidate in 1989 under the banner of the Democratic Convergence, a coalition of leftist parties allied with the guerrillas.

At his death Mr. Ungo, who had lived in self-imposed exile in Panama from 1980 to 1987, was on the ballot for a seat in El Salvador's National Assembly in elections scheduled nine days from now.

"Just last August Mr. Ungo celebrated 30 years of political effort on behalf of popular causes," said Rene Flores, an official of the National Revolutionary Movement. "The truth is that in El Salvador today there is no other leader or politician with the comparable stature, maturity or capacity to contribute to the achievement of a lasting peace."

Guillermo Manuel Ungo was born into an upper-middle-class family that owned a printing plant in San Salvador. He attended a Roman Catholic high school and, when he was 18 years old, was sent to the University of Pittsburgh to study in the hope that he would take over the family business.

But when he returned to El Salvador in 1952 he decided instead to study law at the National University. It was there, as a member of a student movement known as Catholic Action, that he first became involved in politics.

In the 1960's he was part of a group of social democratic intellectuals who eventually formed the National Revolutionary Movement, and in 1969 he became the movement's secretary general. Three years later he ran unsuccessfully for vice president on a ticket headed by Jose Napoleon Duarte.

In October 1979, when Gen. Carlos Humberto Romero was ousted by young army officers, Mr. Ungo was named to a new five-man military junta. But only 10 weeks later, along with other liberals and leftists who complained that promised reforms were being blocked by the army high command, he resigned and joined the opposition.

At the end of 1979, after he had received death threats and the family printing plant had been bombed, Mr. Ungo fled El Salvador, settling with his wife and three teen-age children in Panama City. He dedicated himself full time to the political struggle against the junta.

In November 1987, in the middle of the civil war, he returned to El Salvador in an effort to restore a place for the left in his country's elective politics.

After the defeat of his Democratic Convergence in 1989, he was said to conclude that while he had sought to bring about peaceful change in El Salvador's politics, he was seen by the public as a front man for the rebels rather than a politician lending legitimacy to the democratic system.

His wife and three children survive.