In an age when property owners in every neighborhood struggle to fill empty storefronts, a quiet renaissance is taking shape on the most unlikely of stretches: San Francisco’s perennially down-on-its-luck Sixth Street.

The two-block corridor between Market and Howard streets is attracting a wave of entrepreneurs who see urban vitality and density, not to mention affordable rents, where others see blight and human suffering. Over the past year, Sixth Street, and the alleyways adjacent to it, have added a new cafe and art gallery, a new bar, a Jewish bakery, a grilled-cheese shop, a milk-tea spot, and a wig store.

And there’s more to come: An additional five retailers and food establishments are building out spaces, including Thrasher, the pioneering San Francisco skateboard magazine and apparel company that has never had its own store in its 37-year history despite cultivating a brand known around the world. Also coming this spring and summer: a store from Create Skate, another local skateboard brand; a Nepalese restaurant; a kosher falafel place; and a Greek restaurant.

Thrasher owner Tony Vitello said he’d been thinking about opening a brick-and-mortar venue for a few years — a small store that doubles as an archive. But despite having plenty of options — he was courted by landlords in the city as well as Los Angeles and Las Vegas — nothing quite fit the creative, antiestablishment, DIY culture Thrasher has been cultivating since publishing its first magazine in 1981.

In the end, Vitello fell in love with a spot that few real estate professionals might have recommended: a dingy, hole-in-the-wall storefront at 66 Sixth St. Vitello liked the address — the sign-of-the-devil triplet of sixes — and appreciated that it was about as far as you could get from a trendy retail corridor like Haight Street or Valencia Street.

“It was on Page 12 of this real estate website, and there wasn’t even a photo,” he recalled. “I went down to the real estate office. ... They were like, ‘Why do you want this place? We don’t even understand why you want to be in the area. Have you looked in the Mission?’”

Vitello had and wasn’t interested. Thrasher is set to open later in the spring.

Sixth Street serves a crucial role in the city’s housing and social service infrastructure, a refuge for the city’s poor in rapidly gentrifying South of Market. The two blocks south of Market Street are home to 24 residential hotels with 1,507 rooms, with hundreds more low-income units in apartment buildings such as the Bayanihan House at 88 Sixth St. and the new Bill Sorro Community at 200 Sixth St.

Hotels like the Knox, the Rose and the Dudley all house formerly homeless people. There are places both for intravenous drug users to get clean needles and for drug recovery services. There are rooms set aside for former prison inmates.

But the concentration of poverty, social services and housing density fuels the perception — sometimes warranted, sometimes not — that Sixth Street is out of control, its sidewalks clogged and rancid, its alleyways littered with human waste and needles. Many San Francisco residents avoid the street unless it’s to visit Tu Lan, the classic Vietnamese greasy spoon that opened in 1977.

While acknowledging the challenges, the new business owners say they embrace the street, flaws and all. Bobby Valentino Sanchez, who opened the cafe and art gallery Pentacle right next to the future Thrasher, said he was drawn to Sixth Street’s eclectic liveliness.

“For me, this is the spot where I get to live out my dream,” said Sanchez, who has spent 20 years in the coffee business, including a decade at Four Barrel. “It’s the part of the city that feels the most like a city. It’s denser. If you are going to be a new business, it makes sense to be where there is more foot traffic.”

Liz Hafalia / The Chronicle

It’s also the spot where the rents are among the most affordable in the city. Rents for unimproved commercial space on Sixth Street can be as little as $1.50 or $2 a square foot — about one-third of what a similar space on Valencia Street would cost, according to Nancy Conover, who handles leasing for Mercy Housing, which owns several properties on Sixth Street.

Sanchez allows that Sixth Street “is pretty intense,” but says, “The neighborhood has been welcoming.

“The residents who live in the SROs (single-room-occupancy hotels) don’t want to walk past empty storefronts,” he said. “I do get some people from the SROs. That’s the great thing about coffee, even fancy coffee — $3 might be more than the $1.50 cup down the street, but it’s still pretty accessible.”

A few doors to the south is the Rumpus Room, a new bar that opened this month with an Art Deco theme in keeping with the interior’s 1935 design.

It has a half door open to the street, and, unlike the other drinking establishments on Sixth Street, which open at 5 p.m. or later, the Rumpus Room starts pouring at noon, said co-owner Roxzann De Marco.

“I wanted to be open every day at noon, even if nobody is here,” said De Marco, a graphic designer and video artist. “I definitely wanted to open a neighborhood-feeling bar. I didn’t want to open something too fancy.”

The influx of new businesses comes as much more housing is planned for the area. Four developments totaling 400 units have been approved along Sixth Street between Harrison and Howard streets. Meanwhile, the Tenderloin Neighborhood Development Corp. is close to opening 83 affordable units on Mission near Sixth, and a market-rate building recently started leasing 47 new lofts at 570 Jessie near Sixth. An additional 1,500 units are planned on the Market Street blocks adjacent to Sixth Street.

Conover said the influx of new businesses — along with the prospect of more residents — is starting to make recruiting businesses to Sixth Street a bit easier. She recently signed leases with two new tenants at the Bill Sorro Community building: a place owned by Binita Pradhan, a Nepalese chef who has a loyal following at her kiosks in the Financial District, the Ferry Building and Fort Mason; and Falafel Ness, a casual kosher Middle Eastern spot.

“We probably had 50 different tenants look at those spaces,” Conover said. “Sixth Street is still tough, but I really do feel like it’s turning.”

Falafel Ness will be part of a fledgling cluster of Jewish businesses and community spaces. In the past year Chabad SoMa Shul: Positively Sixth Street, a community center and synagogue, opened, as well as Frena, a kosher bakery started by Israeli transplants who bemoaned the Bay Area’s lack of savory treats such as the bureka and sambusak that are found in Tel Aviv or Jerusalem. Falafel Ness owner Ariel Erik Sharabi, a native of Israel who in the 1980s owned a falafel place on Geary Boulevard in the Richmond and a pita bakery in Walnut Creek, said he was persuaded to open up by his friends from Chabad and Frena.

“I’m going to tell you we’re going to have the best products, the biggest sandwiches, the best hummus and reasonable prices,” Sharabi said. “Chabad is pushing. Frena is pushing. We’re all going to work together to make Sixth Street better.”

Rabbi Yosef Langer of Chabad said the relocation from the Richmond District onto Sixth Street has forced him to confront some stark problems. Every day, he sees crack pipes and needles strewn all over the ground, addicts shooting up against his building,“vulgarity” and screaming at all hours. He said the street can be unpleasant, but he sympathizes with the folks who have no place better to go.

“It is not easy,” he said. “The security is tough. You have to keep your eyes open. But most people down there just want a smile and a ‘good morning.’ Even the dogs need a smile and a ‘good morning.’”

Before he died in December, Mayor Ed Lee often talked about Sixth Street, making its revival a priority of the Office of Economic and Workforce Development, which provided lease negotiation services for the majority of the new businesses, and helped fund facade and sign improvements.

“Mayor Lee was deeply committed to seeing new neighborhood-serving businesses open on Sixth Street,” said Joaquin Torres, deputy director of the agency. “He would have been thrilled to celebrate all of these small-business owners making the choice to open on Sixth Street.”